Filtern
Dokumenttyp
- Vortrag (722)
- Zeitschriftenartikel (423)
- Beitrag zu einem Tagungsband (218)
- Posterpräsentation (65)
- Forschungsbericht (11)
- Buchkapitel (7)
- Dissertation (7)
- Sonstiges (6)
- Forschungsdatensatz (4)
- Monografie (3)
- Sammelband (Herausgeberschaft für den kompletten Band) (1)
- Beitrag zu einem Sammelband (1)
- Tagungsband (Herausgeberschaft für den kompletten Band) (1)
- Handbuch (1)
- Zeitschriftenheft (Herausgeberschaft für das komplette Heft) (1)
Sprache
- Englisch (1020)
- Deutsch (442)
- Russisch (5)
- Mehrsprachig (2)
- Spanisch (2)
Schlagworte
- Additive manufacturing (104)
- Additive Fertigung (96)
- Laser beam welding (96)
- Additive Manufacturing (87)
- Welding (83)
- Hydrogen (80)
- Eigenspannungen (64)
- Residual stress (53)
- Wear (53)
- Wasserstoff (52)
- Friction (50)
- Hochfester Stahl (43)
- Microstructure (43)
- Schweißen (43)
- Ultraschallunterstütztes Fräsen (40)
- MAG-Schweißen (38)
- Thermography (35)
- Mechanical properties (34)
- Laser powder bed fusion (33)
- Residual stresses (32)
- Solidification cracking (29)
- LIBS (27)
- Tribology (27)
- Laser metal deposition (24)
- TIG welding (24)
- Hochfester Feinkornbaustahl (23)
- Niobium carbide (23)
- Ultrasonic-assisted milling (23)
- Creep-resistant steel (21)
- Oberflächenintegrität (21)
- High-strength steels (20)
- In situ measurement (20)
- Legierungsmodifikation (20)
- Numerical simulation (20)
- Residual Stress (20)
- Diffusion (19)
- Wärmeführung (19)
- Hydrogen assisted cracking (18)
- L-PBF (18)
- Laser Powder Bed Fusion (18)
- Neutron diffraction (18)
- Surface integrity (18)
- Laser implantation (17)
- AGIL (16)
- Digitalisierung (16)
- Fatigue (16)
- Laserstrahlschweißen (16)
- Cyclic R-curve (15)
- Duplex stainless steel (15)
- High-strength steel (15)
- Kaltrisssicherheit (15)
- Numerical modeling (15)
- Process monitoring (15)
- Weld pool shape (15)
- 316L (14)
- Alloy 36 (14)
- Stress relief cracking (14)
- AlSi10Mg (13)
- Digitalisation (13)
- Fracture mechanics (13)
- Laser-induced periodic surface structures (LIPSS) (13)
- Open science (13)
- Polymers (13)
- Steel (13)
- Werkzeugverschleiß (13)
- AM (12)
- Diffraction (12)
- Heat treatment (12)
- High-entropy alloy (12)
- Hybrid laser-arc welding (12)
- Inconel 718 (12)
- NbC (12)
- Porosity (12)
- Post weld heat treatment (12)
- Reparatur (12)
- Thermografie (12)
- Ti-6Al-4V (12)
- TiB2 (12)
- WEZ-Erweichung (12)
- Alloy modification (11)
- DED (11)
- High Entropy Alloy (11)
- Hochfeste Feinkornbaustähle (11)
- Hydrogen Embrittlement (11)
- Laser hybrid welding (11)
- Laser welding (11)
- Submerged arc welding (11)
- Windenergie (11)
- X-ray diffraction (11)
- Fügetechnik (10)
- Hardness (10)
- Hybrid laser arc welding (10)
- LTT (10)
- MVT (10)
- Machining (10)
- Research data management (10)
- Surface texturing (10)
- Thick-walled steel (10)
- WAAM (10)
- i-TRIBOMAT (10)
- AISI 316L (9)
- Deep penetration laser beam welding (9)
- Element transport (9)
- Fatigue crack propagation threshold (9)
- Fatigue strength (9)
- Fatigue tests (9)
- Hot cracking (9)
- Infrared thermography (9)
- Laser Metal Deposition (9)
- Mikrolegierungseinfluss (9)
- Restraint (9)
- Stainless Steel (9)
- Tribologie (9)
- Tubular X-joints (9)
- AISI D2 (8)
- Bruchmechanik (8)
- Characterisation (8)
- Forschung (8)
- Harmonisation (8)
- Heat control (8)
- High strength steel (8)
- Implant-Test (8)
- Kaltriss (8)
- Laserhybridschweißen (8)
- Magnetohydrodynamics (8)
- Numerical modelling (8)
- Offshore (8)
- Oxidation (8)
- Pipeline (8)
- Resistance spot welding (8)
- Solidification (8)
- Temperature (8)
- ToF-SIMS (8)
- Weld pool dynamics (8)
- Auftragschweißen (7)
- Carrier gas hot extraction (7)
- Charpy impact toughness (7)
- Chemical composition (7)
- Component assessment (7)
- Cryogenic temperature (7)
- Digital image correlation (7)
- Digitalization (7)
- Electromagnetic backing (7)
- Electromagnetic forces (7)
- FEM (7)
- Fatigue crack growth (7)
- Friction stir welding (7)
- High power laser beam welding (7)
- Hydrogen embrittlement (7)
- Joining dissimilar materials (7)
- Kaltrisse (7)
- LMD (7)
- Magnetic field (7)
- Medium Entropy Alloys (7)
- Nickel (7)
- Open data (7)
- Reparaturschweißen (7)
- Residual Stresses (7)
- Schwingfestigkeit (7)
- Selective Laser Melting (SLM) (7)
- Selective laser melting (SLM) (7)
- Simulation (7)
- Steel and aluminium (7)
- Thermal cycles (7)
- Tool wear (7)
- UP-Schweißen (7)
- WRC 1992 diagram (7)
- Wärmenachbehandlung (7)
- Austenitic stainless steel (6)
- Austenitic stainless steels (6)
- Automated manufacturing (6)
- Bauteilprüfung (6)
- Bulging effect (6)
- Cermet (6)
- Computed Tomography (6)
- Computed tomography (6)
- Cracking (6)
- Critical strain (6)
- DED-arc (6)
- Deep penetration (6)
- Duplex (6)
- Fatigue crack propagation (6)
- Fracture Mechanics (6)
- Gefügedegradation (6)
- Gusseisen mit Kugelgraphit (6)
- Heat accumulation (6)
- Hot stamping (6)
- ISO 3690 (6)
- Interlaboratory tests (6)
- Keyhole mode welding (6)
- Large-scale test (6)
- Laser Powder Bed Fusion (L-PBF) (6)
- Laser-Pulver-Auftragschweißen (6)
- Laserimplantation (6)
- Lubricants (6)
- Master Curve (6)
- Mechanical Engineering (6)
- Notch stress approach (6)
- PBF-LB/M (6)
- Partial penetration (6)
- Process parameters (6)
- Prüfverfahren (6)
- Reibung (6)
- Round robin tests (6)
- Rührreibschweißen (6)
- Selective Laser Melting (6)
- Studie (6)
- Turbine disk (6)
- Varestraint test (6)
- Welding simulation (6)
- Zerspankräfte (6)
- Zerspanung (6)
- Ökobilanzierung (6)
- 3D printing (5)
- AFM (5)
- Additive Manufacturing (AM) (5)
- Additive manufacturing (AM) (5)
- Arc welding (5)
- Artificial neural network (5)
- Crack (5)
- Crack closure (5)
- Cutting tool (5)
- Digital Image Correlation (5)
- Direct Energy Deposition (5)
- Directed Energy Deposition (5)
- Eisenaluminid (5)
- End crater (5)
- Erstarrungsriss (5)
- GMA welding (5)
- Gaseous hydrogen (5)
- Grain refinement (5)
- Gründungsstrukturen (5)
- Heißriss (5)
- Heißrisse (5)
- High entropy alloy (5)
- Hochentropie Legierung (5)
- Hochfest (5)
- Hot steam (5)
- Hybrid Laser Arc Welding (5)
- Hydrogen-assisted cracking (5)
- Kitagawa-Takahashi diagram (5)
- Künstliche Intelligenz (5)
- LIBS TIG welding (5)
- Laser energy distribution (5)
- Leichtbau (5)
- Liquid metal embrittlement (5)
- Low Cycle Fatigue (5)
- Mechanics of Materials (5)
- Modifizierter Sprühlichtbogen (5)
- Neutron Diffraction (5)
- Neutron imaging (5)
- Numerical Simulation (5)
- Numerical process simulation (5)
- Pipelines (5)
- Polymer composites (5)
- Qualitätssicherung (5)
- Repair-welding (5)
- Research (5)
- Review (5)
- SSRT (5)
- Schadensanalyse (5)
- Sintering (5)
- Spannungsrelaxationsriss (5)
- Structural stress approach (5)
- Tensile properties (5)
- Thermal desorption analysis (5)
- Thermodynamische Simulation (5)
- Thick-plate welding (5)
- WelDX (5)
- Weldments (5)
- Widerstandspunktschweißen (5)
- Wind energy (5)
- X-ray and Neutron Diffraction (5)
- X38CrMoV5-3 (5)
- 3D Druck (4)
- AISI 304L (4)
- Acoustic emission (4)
- Atomic Forc Microscopy (4)
- Atomic force microscopy (4)
- Automatisierte Fertigung (4)
- Bulge effect (4)
- CNN (4)
- Cold cracking (4)
- Cold cracking safety (4)
- Constraint (4)
- Contact resonance (4)
- Cutting tools (4)
- Cyclic R-Curve (4)
- DED-Arc (4)
- Defects (4)
- Deuterium (4)
- Dickblech (4)
- Diffusible hydrogen (4)
- Direct energy deposition (4)
- Directed energy deposition (4)
- Ductile cast iron (4)
- Dynamic Fracture Toughness (4)
- EBSD (4)
- Elastic modulus (4)
- Electrochemical permeation (4)
- Elektromagnetische Schmelzbadbeeinflussung (4)
- Endkrater (4)
- Evaporation (4)
- Fail-safe (4)
- Fatigue life (4)
- Femtosecond laser (4)
- Forschungsdatenmanagement (4)
- Fracture toughness (4)
- GMAW (4)
- Gap bridgeability (4)
- Heat conduction (4)
- High Entropy Alloys (4)
- High-strength structural steel (4)
- High-strength structural steels (4)
- Highspeed-plasma-laser-cladding (4)
- Hochentropielegierung (4)
- Hollow Specimen Technique (4)
- ICP-MS (4)
- IN718 (4)
- In-situ Monitoring (4)
- Inter layer time (4)
- Intrinsischer Schwellenwert gegen Ermüdungsrissausbreitung (4)
- KI (4)
- Kaltrissprüfung (4)
- Kerbschlagzähigkeit (4)
- Keyhole dynamics (4)
- LPBF (4)
- Laser beam melting (LBM) (4)
- Laser powder bed fusion (L-PBF) (4)
- Liquid Metal Embrittlement (4)
- Martensite (4)
- Mathematical modeling (4)
- Microstructure characterization (4)
- Mikrostruktur (4)
- Multi-physical modeling (4)
- Multi-principal element alloys (4)
- Niobium carbide (NbC) (4)
- Offshore Windenergieanlagen (4)
- Oscillating magnetic field (4)
- PEEK (4)
- Plasma-Transferred-Arc (4)
- Plasma-transferred arc welding (4)
- Position detection (4)
- Potentiodynamic Polarization (4)
- ProMoAM (4)
- Process simulation (4)
- Properties (4)
- Quality assurance (4)
- Qualitätsinfrastruktur (4)
- Ray tracing (4)
- Repair welding (4)
- Restlebensdauer (4)
- Rundnaht (4)
- SIMS (4)
- SLM (4)
- Safety (4)
- Scanning Kelvin Probe Force Microscopy (4)
- Schadenstolerante Bauteilauslegung (4)
- Shear modulus (4)
- Stainless steel (4)
- Surface modification (4)
- Synchrotron (4)
- TEKKEN-Test (4)
- Technical crack detection (4)
- Texture (4)
- Thermisches Ausfugen (4)
- Thermo-fluid flow (4)
- ThermoCalc (4)
- Titanium (4)
- Toughness (4)
- Transport cask (4)
- Tribofilm (4)
- Varestraint (4)
- Varestraint-Test (4)
- WIG-Schweißen (4)
- Weld metal (4)
- Wood (4)
- Young's modulus (4)
- Zyklische R-Kurve (4)
- 100Cr6 (3)
- 9%Ni steel (3)
- Ageing (3)
- Aging (3)
- Alumina (3)
- Applications (3)
- Aqueous Corrosion (3)
- Artungleiche Werkstoffe (3)
- Aufgelöste Tragstrukturen (3)
- Boundary element method (3)
- Bulge formation (3)
- Bulging (3)
- Burst (3)
- CT (3)
- Chunky graphite (3)
- Circumferential weld (3)
- Cobalt (3)
- Cold Spray (3)
- Component test (3)
- Corrosion (3)
- Crack propagation (3)
- Cryogenic steel (3)
- Crystal branch development (3)
- DVS (3)
- Data fusion (3)
- Data-fusion (3)
- Database (3)
- Defokussierung (3)
- Deposition welding (3)
- Dilatometry (3)
- Dimensional accuracy (3)
- Dissimilar metal weld (3)
- Dissimilar metal weld (DMW) joint (3)
- Dissimilar metal weld overlays (3)
- Distortion (3)
- Ductile Cast Iron (3)
- Duplex Stainless Steel (3)
- Duplex stainless steels (3)
- Dynamische Beanspruchung (3)
- Edge quality (3)
- Eigenspannung (3)
- Elastomers (3)
- Electrochemical Impedance Spectroscopy (3)
- Electromagnetic Weld Pool Support (3)
- Electromagnetic weld pool support (3)
- Electron backscattered diffraction (3)
- Electron beam welding (3)
- Elektromagnetische Schmelzbadunterstützung (3)
- Endurance limit (3)
- Equivalent heat source (3)
- Erneuerbare Energien (3)
- Experimental procedure (3)
- Fatigue limit (3)
- Fe3Al (3)
- Feinkornbaustahl (3)
- Femtosecond laser ablation (3)
- Fortschrittsbericht (3)
- Fracture (3)
- Full Penetration (3)
- Fügetechnologie (3)
- Gas metal arc welding (3)
- Grain size (3)
- Gutachten (3)
- HAZ-softening (3)
- Hardmetal (3)
- Heat Treatment (3)
- High-strength Steels (3)
- Hohlzugprobe (3)
- Hollow specimen (3)
- Hot crack (3)
- Hot-Stamping (3)
- Hybrid components (3)
- Hybrid repair (3)
- Hydrogen diffusion (3)
- Hydrogen measurement (3)
- Implant test (3)
- In situ (3)
- In situ monitoring (3)
- In-situ monitoring (3)
- In-situ process monitoring (3)
- Keyhole collapse (3)
- Korrosionsschutz (3)
- Kupferazid (3)
- LCF (3)
- LME (3)
- LPA (3)
- Laser (3)
- Laser Beam Welding (3)
- Laser Pulver Auftragsschweißen (3)
- Laser Welding (3)
- Laser beam melting (3)
- Laser dispersing (3)
- Life Cycle Assessment (3)
- Local fatigue approaches (3)
- Lubricated sliding (3)
- Lubrication (3)
- MSG-Schweißen (3)
- Master Curve Concept (3)
- Master Curve-Konzept (3)
- Measurement (3)
- Mechanical mismatching (3)
- Mechanische Eigenschaften (3)
- Medium entropy alloy (3)
- Mediumentropie Legierung (3)
- Mediumentropielegierung (3)
- Melt pool dinamics (3)
- Metals and Alloys (3)
- Methane (3)
- Microalloying influences (3)
- Model calibration (3)
- Molten pool dynamics (3)
- Multi-physical modelling (3)
- Multielementlegierungen (3)
- Multispectral thermography (3)
- NDT (3)
- Neutron radiography (3)
- Ni alloy (3)
- Numerische Simulation (3)
- Offshore Windenergie (3)
- Online Process Monitoring (3)
- Optical Tomography (3)
- Optical flow (3)
- Optical tomography (3)
- Oscillating vapor plume (3)
- Overspeed (3)
- Periodic solidification pattern (3)
- Phase transformation (3)
- Pipeline steel (3)
- Plasma-Pulver-Auftragschweißen (3)
- Polymer materials (3)
- Presshärten (3)
- Prozesskette (3)
- Prozessmonitoring (3)
- Prozessüberwachung (3)
- Pufferschichten (3)
- Quality Assurance (3)
- Repair (3)
- Reproducibility (3)
- Residual stress analysis (3)
- Rissarrest (3)
- Schallemission (3)
- Schweißeigenspannungen (3)
- Schweißverfahren (3)
- Selective laser melting (3)
- Short crack (3)
- Sliding (3)
- Spannungsrelaxationsrisse (3)
- Sprödbruch (3)
- Stahl und Aluminium (3)
- Structural Integrity (3)
- Structural integrity (3)
- Surface functionalization (3)
- TEKKEN (3)
- TES (3)
- Temperature emissivity separation (3)
- Tensile strength (3)
- Thick Materials (3)
- Transient heat transfer (3)
- Tungsten carbide (3)
- Turning (3)
- Umlaufkühler (3)
- Umweltwirkungen (3)
- Vacuum (3)
- Verschleiß (3)
- Viscoplasticity (3)
- Wasserstofftechnologien (3)
- Weldability (3)
- Wire arc additive manufacturing (3)
- Zerstörungsfreie Prüfung (3)
- Überlappbereich (3)
- (U)HMWPE (2)
- 13CrMoV9-10 (2)
- AI (2)
- ASTM E1921 (2)
- ASTM E647 (2)
- Abdichtbauwerk (2)
- Abrasion (2)
- Accelerometers (2)
- Achsschenkel (2)
- Adaptives Schweißen (2)
- Advanced high strength steel (2)
- Advanced high strength steels (2)
- Aerosol measurements (2)
- Al/Mg alloys (2)
- Aluminum alloys (2)
- Analysis (2)
- Analytisches Modell (2)
- Arc Welding Automation (2)
- Arc welding automation (2)
- Archard's law (2)
- Atomic Force Microscopy (2)
- Austenite-to-martensite transformation (2)
- Austenitic Stainless Steel (2)
- Automated welding (2)
- Automatisierte schweißtechnische Fertigung (2)
- Bauteilauslegung (2)
- Bauteilbewertung (2)
- Bead-on-plate welds (2)
- Bending tests on pipe segments (2)
- Bohrlochsonde (2)
- Bragg-edge imaging (2)
- Bridging voids (2)
- Brittle fracture (2)
- Bruchmechanische Auslegung (2)
- Build direction (2)
- Build-up Orientation (2)
- Bulge (2)
- CASTOR-Behälter (2)
- CFD-model (2)
- CNG (2)
- CTS (2)
- Calibration free (2)
- Capability (2)
- Carbon steel (2)
- Carbonitride (2)
- Ceramic (2)
- Characterization (2)
- Co-Cr-alloy (2)
- Coarse-grained heat-affected zone (2)
- Coefficient of Friction (2)
- Columnar crystal growth (2)
- Composites (2)
- Computed tomography (CT) (2)
- Condensed Matter Physics (2)
- Condition monitoring (2)
- Continous monitoring (2)
- Copper powder particles (2)
- Crack closure effect (2)
- Crack growth (2)
- Crack initiation (2)
- Crack-closure (2)
- Creep (2)
- Creep behavior (2)
- Creep resistant steel (2)
- Creep-resisting materials (2)
- Crystallographic texture (2)
- Cyclic J-integral (2)
- Cyclic R-curve analysis (2)
- DED-EB (2)
- DLC (2)
- Damage tolerance (2)
- Data evaluation methods (2)
- Data preparation (2)
- Datenbank (2)
- Debye-Waller-Faktor (2)
- Debye–Waller factor (2)
- Defekte (2)
- Degradation (2)
- Design for Additive Manufacturing (DfAM) (2)
- Digital (2)
- Digital transformation (2)
- Direct Laser Metal Deposition (2)
- Direct laser deposition (2)
- Directed Enery Deposition (2)
- Distributed acoustic sensing (2)
- Divergente Ausbildung der Wärmeeinflusszone (2)
- Dual phase steel (2)
- Ductile iron (2)
- Duplex AISI 2205 (2)
- Duplex steels (2)
- Durability (2)
- Dynamic fracture toughness (2)
- Dynamische Bruchzähigkeit (2)
- EBAM (2)
- EDS (2)
- Effective crack propagation data (2)
- Einspanngrad (2)
- Electrical conductivity (2)
- Electromagnetic support (2)
- Electron backscatter diffraction (2)
- Elektromagnetische Schmelzbadsicherung (2)
- Elektronenstrahlschweißen (2)
- Embedded electronics (2)
- Embrittlement (2)
- End-crater (2)
- Environmental conditions (2)
- Ermüdung (2)
- Ermüdungsfestigkeit (2)
- Ermüdungsrisswachstum (2)
- Erstarrungsrisse (2)
- Europäisches Tribologie-Zentrum (2)
- Expansion joint (2)
- Experiment (2)
- Experimental design (2)
- Experimental determination (2)
- Explosion (2)
- FE-model (2)
- FGM (2)
- Fahrrad (2)
- Failure Assessment Diagram (2)
- Fatigue Crack Growth (2)
- Fatigue Crack Propagation (2)
- Fatigue Strength (2)
- Fatigue damage (2)
- Fatigue properties (2)
- Femtosecond laser processing (2)
- Ferritic spheroidal graphite cast iron (2)
- Ferromagnetischer Stahl (2)
- Fiber optic sensing (2)
- Fibre optic acoustic sensing (2)
- Filler material distribution (2)
- Filler wire mixing (2)
- Finite element analysis (2)
- Finite element method (2)
- Finite element simulation (2)
- Flüssigmetallinduzierte Rissbildung (2)
- Force distance curve (2)
- Force-distance curves (2)
- Four-point bending test (2)
- Fractography (2)
- Fracture resistance (2)
- Fraktographie (2)
- Frequenzanalyse (2)
- Fräsen (2)
- Fuel economy (2)
- Full penetration (2)
- Fume (2)
- Fusion zone size (2)
- GMA Welding (2)
- GTAW (2)
- Gas tungsten arc welding (GTAW) (2)
- General Materials Science (2)
- Generative Fertigung (2)
- Grade S960QL steel (2)
- Green Deal (2)
- H2Safety@BAM (2)
- HAZ-Softening (2)
- HEA (2)
- HSLA (2)
- HSLA steel (2)
- Hard metals (2)
- Hardly separable problem (2)
- Hartstoffphasen (2)
- Heat treatments (2)
- Heat-affected zone (2)
- Heissrisse (2)
- High Cycle Fatigue (2)
- High Temperature Testing (2)
- High strength steels (2)
- High-Pressure Gaseous Hydrogen (2)
- High-power laser (2)
- High-power laser beam (2)
- High-power laser beam welding (2)
- High-pressure (2)
- High-resolution camera (2)
- High-strength filler metals (2)
- Hochdruck (2)
- Hochleistungsschweißen (2)
- Hochtemperaturwerkstoffe (2)
- Hollow specimen technique (2)
- Holz-Stahl-Kontakte (2)
- Hot Cracks (2)
- Hybrid Part (2)
- Hybrid welding (2)
- Hybridschweißen (2)
- Hydrogen Assisted Cracking (HAC) (2)
- Härteprüfung nach Vickers (2)
- Höherfeste Feinkornbaustähle (2)
- Höherfester Feinkornbaustahl (2)
- Höherfester Stahl (2)
- IBESS (2)
- ISO 12108 (2)
- Image processing (2)
- In situ strain (2)
- In-service (2)
- In-situ (2)
- Ionic liquid (2)
- Iron aluminide (2)
- Irradiation (2)
- Jacket Support Structures (2)
- Joint sealing (2)
- Kaltrissbildung (2)
- Kerbschlagarbeit (2)
- Keyhole mode laser beam welding (2)
- Keyhole porosity (2)
- Korrelation (2)
- L-PBF 316L (2)
- LDX (2)
- LIMS (2)
- LIPSS (2)
- LNG (2)
- LTT (Low Transformation Temperature) (2)
- LTT Weld Filler Materials (2)
- LTT weld filler materials (2)
- LTT-Zusatzwerkstoff (2)
- Laboratory specimens (2)
- Lack-of-fusion (2)
- Large electrical high-voltage machine (2)
- Laser Metal Deposition (LMD) (2)
- Laser Powder Bed Fusion (PBF-LB/M) (2)
- Laser ablation (2)
- Laser beam welding (LBW) (2)
- Laser energy absorption (2)
- Laser metal deposition (LMD) (2)
- Laser-Hybridschweißen (2)
- Laser-metal-deposition (2)
- Laserpulverauftragschweißen (2)
- Laserstrahlschmelzen (2)
- Leak detection (2)
- Leakage Rate (2)
- Lebensdauer (2)
- Lichtbogensensorik (2)
- Life cycle assessment (2)
- Lightweight Design (2)
- Liquation Cracking (2)
- Localized laser dispersing (2)
- Longitudinal Wave (2)
- Low heat input GMA welding (2)
- Low transformation temperature (LTT) steel (2)
- Lubricant additives (2)
- MAG welding (2)
- MHD (2)
- MSG-Engspaltschweißen (2)
- Matching ferritic welding electrode (2)
- Material defects (2)
- Material modeling (2)
- Material transport (2)
- Materialkompatibilität (2)
- Materialuntersuchung (2)
- Mechanical behavior (2)
- Melt pool dynamics (2)
- Metal (2)
- Metal mixing (2)
- Metal vapor (2)
- Metallschutzgasschweißen (2)
- Metallsulfide (2)
- Metallurgie (2)
- Micro-shrinkages (2)
- Microbiologically influenced corrosion (2)
- Microstructure and texture (2)
- Mikrolegierungseinflüsse (2)
- Minimum Waiting Time (2)
- Misalignment of the edges (2)
- Modellierung (2)
- Modification of structural morphology (2)
- Molten pool (2)
- Molten pool behaviour (2)
- Moving mesh (2)
- Multiple cracks (2)
- Multiple principal element alloy (2)
- Multiple reflections (2)
- Nachwärmung (2)
- Nahtgeometrie (2)
- NbC cermets (2)
- Neuronales Netz (2)
- Neuronales Netzwerk (2)
- Neutron (2)
- Neutronenbeugung (2)
- NiCrBSi (2)
- Nickel alloys (2)
- Niobium alloying (2)
- Non-metallic inclusions (2)
- Offshore Wind (2)
- Offshore steel grade (2)
- Offshore wind (2)
- Optical measurement (2)
- Optische Tomografie (2)
- PAG (2)
- PBF-LB/M/316L (2)
- PBF/LB-M (2)
- PWHT (2)
- Particle gas emission (2)
- Path planning (2)
- Penetration depth (2)
- Performance testing (2)
- Phasenumwandlung (2)
- Photoresist (2)
- Pipe manufacturing (2)
- Pipeline monitoring (2)
- Pipeline steel X120 (2)
- Pitting (2)
- Plasma (2)
- Plasma-cutting (2)
- Plastic deformation (2)
- Plume (2)
- Polymere (2)
- Pores (2)
- Post-weld heat treatment (2)
- Powder Bed Fusion (2)
- Pre-weld Preparation (2)
- Preheating (2)
- Process chain (2)
- Process parameter optimization (2)
- Pulsed laser beam welding (2)
- Quantification (2)
- Querzugversuch (2)
- RSW (2)
- Radioactive Waste (2)
- Raman spectroscopy (2)
- Ray tracing method (2)
- Ray-tracing (2)
- Recognition (2)
- Refill friction stir spot welding (2)
- Reheat cracking (2)
- Repair Welding (2)
- Repair of gas turbine blades (2)
- Representative specimens (2)
- Ressidual stress (2)
- Rissbildung in Stahl (2)
- Rissschließeffekte (2)
- Round robin (2)
- S-N curve (2)
- SEM (2)
- SHPB (2)
- SMAW (2)
- SWIR camera (2)
- Scanning kelvin probe force microscopy (2)
- Scattering (2)
- Schadensprävention (2)
- Schallemissionsanalyse (2)
- Schleifen (2)
- Schutzgasschweißen (2)
- Schweißeignung (2)
- Schweißen von hochfesten FKB (2)
- Schweißnahtbewertung (2)
- Schweißverbindungen (2)
- Schweißzusatzmodifikation (2)
- Schwellenwert gegen Ermüdungsrissausbreitung (2)
- Schwer spanbar (2)
- Seal Behavior (2)
- Seam geometry (2)
- Selected Laser Melting (2)
- Selektive-laser-melting (2)
- Semi-finishing (2)
- Ship building (2)
- Short cracks (2)
- Sicherheit (2)
- Single pass welding (2)
- Sliding wear (2)
- Slip-rolling (2)
- Small-scale specimens (2)
- Software (2)
- Solid lubricants (2)
- Solidification craking (2)
- Solubility (2)
- Spatter (2)
- Speed of sound (2)
- Stahl (2)
- Stainless steels (2)
- Standardisation (2)
- Steel 316L (2)
- Steel pipe (2)
- Stoßdämpfer (2)
- Strain measurement (2)
- Strain rate (2)
- Stress corrosion cracking (2)
- Structure (2)
- Struktur Integrität (2)
- Superellipse (2)
- Superelliptic Lamé curves (2)
- Supermartensitic Stainless Steel (SMSS) (2)
- Supportless (2)
- Surface (2)
- Surface roughness (2)
- Surface structuring (2)
- TPU (2)
- Temperature distribution (2)
- Temperature field (2)
- Tensile Properties (2)
- Tensile Test (2)
- Tensile performance (2)
- Tensile testing (2)
- Testing method (2)
- Thermal history (2)
- Thermo-Calc (2)
- Thermo-capillary convection (2)
- Thermographie (2)
- Ti64 (2)
- TiAl5V4 (2)
- TiAl64V (2)
- Time over threshold (2)
- Titan (2)
- Titanium alloy (2)
- Tool steel (2)
- TransHyDE (2)
- Trapping (2)
- Tribologische Daten (2)
- Turbinenscheibe (2)
- Turbulence (2)
- Ultraschall-Echoverfahren (2)
- Ultraschallunterstütztes Zerspanen (2)
- Ultrasonic Transducer (2)
- Ultrasonic assisted machining (2)
- Ultrasonic assisted milling (2)
- Ultrasonic machining (2)
- Ultrasonic vibration (2)
- Unterpulverschweißen (2)
- Vaporization (2)
- Varestraint testing (2)
- Verfahrensvergleich (2)
- Verschleißbeständigkeit (2)
- Verschlussbauwerk (2)
- Vickers hardness (2)
- WAXD (2)
- WEZ Erweichung (2)
- Wasserstoffdegradation (2)
- Wasserstoffunterstützte Kaltrissbildung (2)
- Wear resistance (2)
- Wear volume (2)
- Weld defects (2)
- Weld geometry (2)
- Weld pool (2)
- Weld pool behavior (2)
- Weld pool geometry (2)
- Weld pool shape approximation (2)
- Welded Joints (2)
- Welded joints (2)
- Welding microstructure (2)
- Welding residual stresses (2)
- Welding thermal cycle (2)
- Werkstoffe (2)
- Werkzeuglebensdauer (2)
- Wire Arc Additive Manufacturing (2)
- Wire electron beam additive manufacturing (2)
- Wärmebehandlung (2)
- X-ray Diffraction (2)
- Zerspanbarkeitsanalysen (2)
- Zinc coated steel (2)
- Zink (2)
- Zirconia (2)
- Zugeigenschaften (2)
- Zwischenlagenzeit (2)
- hochfester Stahl (2)
- µCT (2)
- Öffentliche Sicherheit (2)
- μCT-analysis (2)
- 100Cr6 (AISI 52100) steel (1)
- 100Cr6 steel (1)
- 100Cr6-Stahl (1)
- 2101 duplex stainless steel (1)
- 2Disk (1)
- 3D Scanning (1)
- 3D-finite element modeling (1)
- 9% Ni Steel (1)
- 9%Ni steel, (1)
- AC magnetic field (1)
- ADXRD (1)
- AFM-Kraft-Abstand-Kurven (1)
- AHSS (1)
- AISI 321 stainless steel (1)
- AM 316L stainless steel (1)
- AM feature integration (1)
- ASTM (1)
- AXRD (1)
- Abrasive wear (1)
- Absorbed energy (1)
- Abtragende Glasbearbeitung (1)
- Accelerator magnets (1)
- Accoustic emission (1)
- Acero 316L (1)
- Acero alta resistencia (1)
- Acoustic Emission (1)
- Acoustic emissions (AE) (1)
- Adaptive MSG-Lichtbogenprozesse (1)
- Adaptive MSG-Lichtbogenschweißprozesse (1)
- Adaptive control (1)
- Adaptive remeshing (1)
- Adaptive welding beam oscillation (1)
- Adative arc welding processes (1)
- Additiv (1)
- Additive (1)
- Additive surface treatment (1)
- Additiver Fertigung (1)
- Additives (1)
- Adhesion (1)
- Adhesion by mechanical interlocking (1)
- Adiabatic compression (1)
- Adiabatic shear bands (1)
- Adjustable pressure rise time (1)
- Adsorption (1)
- Advanced High-Strength Steel (AHSS) (1)
- Advanced high-strength steel (1)
- Advanced high-strength steels (1)
- Al-Mg-Si (1)
- Al-Mg-Si-Legierungen (1)
- Al/Ti dissimilar joints (1)
- AlMg0.7SiTiB filler wire (1)
- AlMgSi Legierungen (1)
- AlSi10Mg alloy (1)
- Alite (1)
- Alkyd resin-based coating (1)
- Alloy (1)
- Alloy 247 (1)
- Alloy 718 (1)
- Alloy concept (1)
- Alloys (1)
- Alternative Kraftstoffe (1)
- Alternative fuels (1)
- Alternative test procedure (1)
- Aluminium Alloy (1)
- Aluminium oxide (1)
- Aluminium-Druckguss (1)
- Aluminium-Druckgusslegierung (1)
- Aluminum (1)
- Aluminum bronze (1)
- Analytical calculation (1)
- Analytical chemistry (1)
- Analytical model (1)
- Analytical solution (1)
- Angle dependency (1)
- Anlagen (1)
- Anlagenbau (1)
- Application properties (1)
- Arc sensor (1)
- Artefact (1)
- Artificial Intelligence (1)
- Artificial intelligence (1)
- Artungleiche Werkstoffe; Elektromagnetische Schmelzbadbeeinflussung; Fügetechnologie; Laserstrahlschweißen; Stahl und Aluminium (1)
- As-built LPBF IN718 alloy (1)
- As-shielded arc welding (1)
- Atmospheric conditions (1)
- Atomic force microscope (1)
- Aufheizrate (1)
- Aufmischung (1)
- Auftriebskräfte (1)
- Ausscheidungsverhalten (1)
- Austenit (1)
- Austenitic (1)
- Austenitic Steels (1)
- Austenitic steel (1)
- Austenitic welding electrode (1)
- Austenitischer Rostfreier Stahl (1)
- Automated arc welding (1)
- Automation (1)
- Automatisierte schweißtechniche Fertigung (1)
- Automobilindustrie (1)
- Automotive (1)
- Automotive application (1)
- BAM Windenergie Fügetechnik (1)
- BMDK (1)
- Backlight (1)
- Bacteria (1)
- Bainitischer Schmiedestahl (1)
- Baustähle (1)
- Bauteiltest (1)
- Bauteilversuch (1)
- Bayesian technique (1)
- Beam oscillation (1)
- Beam oscillations (1)
- Beanspruchungsanalyse (1)
- Bedarf (1)
- Bedeutung (1)
- Behavior (1)
- Bending test (1)
- Beschleunigungssensorik (1)
- Betrieb (1)
- Betriebsfestigkeit (1)
- Beugung (1)
- Bewegtes Gitter (1)
- Biaxial test (1)
- Binder (1)
- Binders (1)
- Biofilms (1)
- Bionik (1)
- Biopolymers (1)
- Biotische/abiotische Faktoren (1)
- Bismuth titanates (1)
- Boundary lubrication (1)
- Bragg-edge (1)
- Bragg-edge neutron 2D imaging (BENI) (1)
- Brazil nut Mesocarp (1)
- Bremsbelag (1)
- Bremsbeläge (1)
- Bruch (1)
- Bruchmechanische Kennwerte (1)
- Bruchmechanische Konzepte (1)
- Bruchzähigkeit (1)
- Build-up strategy (1)
- Bulging effects (1)
- Burn out safety (1)
- C(T)-Proben (1)
- CCT diagrams (1)
- CFD model (1)
- Calculation time (1)
- Camera (1)
- Cantilever microprobe (1)
- Carbide (1)
- Carbidic austempered ductile iron (1)
- Carbon (1)
- Carbon dioxide footprint (1)
- Carrier gas hot extraction (CGHE) (1)
- Catalysis (1)
- CdSe/ZnS quantum Dots (1)
- Cell (1)
- Cellular substructure (1)
- Cellular uptake (1)
- Cemented carbide (1)
- Centerline solidification cracking (1)
- Ceramic matrix composites (1)
- Cermets (1)
- Chapetti’s and IBESS model (1)
- Characterization of corrosion layers (1)
- Charakterisierung (1)
- Charpy Impact Test (1)
- Charpy Transition Curve (1)
- Charpy pendulum impact test (1)
- Chemical compositions (1)
- Chemical corrosion (1)
- Chemische Zusammensetzung, (1)
- Chemische Zusammensetzungen (1)
- Chunky graphite degeneration (1)
- Chunky-Graphit (1)
- Cimensional Accuracy (1)
- Circumferential welds (1)
- Clad steels (1)
- Cleavage Fracture (1)
- Cleavage fracture (1)
- Clinker substitute (1)
- Clustering (1)
- Co (1)
- Co-Cr-Legierung (1)
- Coarse grained heat affected zone (1)
- Coating (1)
- Cobalt-chromium alloy (1)
- Codes and standards (1)
- Coefficient of friction (1)
- Cold Cracking (1)
- Cold cracking and welding (1)
- Cold-welding (1)
- Competence Center (1)
- Competence center (1)
- Complex loading (1)
- Component (1)
- Component Assessment (1)
- Component manufatcturing (1)
- Component-like test (1)
- Composite (1)
- Compositionally complex alloy (1)
- Comprehensive study (1)
- Computational fluid dynamics (1)
- Computer Aided Manufacturing (1)
- Computer vision (1)
- Computertomografie (1)
- Constraint faktor (1)
- Contact fatigue (1)
- Contact pressure (1)
- Contamination (1)
- Contour method (1)
- Control (1)
- Conventional Ni-based austenitic welding electrode (1)
- Conventional and Tubular Specimen (1)
- Conversion of results (1)
- Convolutional Neural Networks (1)
- Convolutional neural network (1)
- Convolutional neural networks (CNN) (1)
- Coolant-free (1)
- Cooling rate (1)
- Coordinate measurement machine (1)
- Core-shell structures (1)
- Correlation microstructure to properties (1)
- Corrosion pits (1)
- Corrosion testing (1)
- Counterface (1)
- Co–Cr-alloy (1)
- Cr-Mo-V steel (1)
- CrMoV-Stahl (1)
- Crack Tip Opening Displacement (CTOD) (1)
- Crack arrest (1)
- Crack closure mechanisms (1)
- Crack driving force (1)
- Crack formation and propagation (1)
- Crack initation (1)
- Crack propagation resistance (1)
- Crack-tip constraint (1)
- Cracking mechanism (1)
- Crater (1)
- Crater wear (1)
- Creep resisting materials (1)
- Creep-resisting steel (1)
- Critical strain rate (1)
- Cross-weld tensile sample (1)
- Crown-abutment connection (1)
- Cryogenic Engineering (1)
- Cryogenic Steel (1)
- Crystal Plasticity Modelling (1)
- Crystal plasticity (1)
- Crystallographic texture control (1)
- CuSn1 (1)
- Current density (1)
- Curvas FCGR (1)
- Curve fitting (1)
- Cutting forces (1)
- Cyclic creep curve (1)
- Cyclic loading (1)
- Cyclic stress-strain curve (1)
- Cylindrical turning (1)
- D7755-11 (1)
- DED-L (1)
- DED-LB (1)
- DEM (1)
- DIC (1)
- DSS (1)
- Damage Tolerance (1)
- Damage prediction (1)
- Damage tolerance assessment (1)
- Damage tolerant component design (1)
- Data Integrity (1)
- Data Sciences (1)
- Data-driven quality assurance (1)
- Dataspace (1)
- Datenmanagement (1)
- Dduplex stainless steel (1)
- Debye waller factor (1)
- Debys-Waller-Factor (1)
- Deep learning (1)
- Defect detection (1)
- Defect prediction (1)
- Defekte Eigenspannung (1)
- Deformation (1)
- Deformed geometry (1)
- Dehydrogenation heat treatment (1)
- Dendrite growth (1)
- Density measurement (1)
- Dental materials (1)
- Deposition rate (1)
- Design of experiments (1)
- Determinación Kth intrínseco (1)
- Diaspore (1)
- Dichtungen (1)
- Die-cast aluminum (1)
- Die-casted aluminum (1)
- Diffraction Elastic Constants (1)
- Diffraction-elastic constants (1)
- Diffusibler Wasserstoff (1)
- Diffusion/diffusivity (1)
- Digital Image Correlation (DIC) (1)
- Digital Twin (1)
- Digital image correlation (DIC) (1)
- Digitale Bildkorrelation (DIC) (1)
- Digitale Qualitätssicherung (1)
- Digitization (1)
- Directed Energy Depositio (1)
- Dislocation density (1)
- Dispersive XAS (1)
- Displacement (1)
- Dissimilar friction stir welding (1)
- Dissimilar joints (1)
- Dissimilar materials (1)
- Distortion simulation (1)
- Distortion upon baseplate removal (1)
- Ditigtal image correlation (1)
- Dritter Körper (1)
- Druckanschwingen (1)
- Druckgasspeicher (1)
- Dry cylindrical turning (1)
- Ductile Cast iron (1)
- Duktiles Gusseisen (1)
- Duktilität (1)
- Dwell-time (1)
- Dynamic fracture (1)
- Dynamic load (1)
- Dynamische Belastung (1)
- Dünnschichten (1)
- EA4T railway axle steel (1)
- EA4T steel (1)
- EDXRD (1)
- EN AW-2618A (1)
- Edge effects (1)
- Editorial Board (1)
- Effect of scanning strategies (1)
- Efficient modelling (1)
- Eigensapnnungen (1)
- Eigenspannungsmessung (1)
- Eindringprüfung (1)
- Einfluss Mikrolegierungselmente Ti und Nb (1)
- Einflussfaktoren (1)
- Einflussfaktoren auf Rissfortschrittsdaten (1)
- Einschlüsse (1)
- Elastic follow-up (1)
- Elastic-plastic fracture mechanics (1)
- Electrical connectors (1)
- Electro-plated nickel coatings (1)
- Electro-thermomechnical model (1)
- Electrochemical corrosion (1)
- Electrode geometry (1)
- Electroless Ni-P (1)
- Electromagnetic (1)
- Electromagnetic field (1)
- Electromagnetic influence (1)
- Electromagnetic stirring (1)
- Electromagnetic supported degassing (1)
- Electromagnetic weld pool support system (1)
- Electron backscatter diffraction (EBSD) (1)
- Electron beam (1)
- Electron microscopy (1)
- Elektonenstrahlschweißen (1)
- Elektromagnetische Badstütze (1)
- Elektromagnetische Porenreduktion (1)
- Elektromagnetische Schmelzbadkontrolle (1)
- Elektromagnetische Schmelzbadstütze (1)
- Elektromagnetsiche Schmelzbadbeeinflussung (1)
- Elemenet transport (1)
- Element distribution (1)
- Elemental Distribution (1)
- Elevated temperatures (1)
- Ellipsometry (1)
- Emisssivity (1)
- Energetic reference parameter (1)
- Energieerzeugung (1)
- Energiespeicherung (1)
- Energy Engineering and Power Technology (1)
- Energy absorption capacity (1)
- Energy parameters of the arc (1)
- Engine oil design (1)
- Engine oil testing (1)
- Entwicklung (1)
- Environment (1)
- Environmental effect (1)
- Environmental effects (1)
- Environmental impact categories (1)
- Equivalent stress concentration factors (1)
- Equivalent volumetric heat source (1)
- Ermüdungslebensdauer (1)
- Ermüdungsriss (1)
- Ermüdungsrissfortschritt (1)
- Error sources analysis (1)
- Ersatzgeometrie (1)
- Explosionsschutz (1)
- FAIR data (1)
- FAT class (1)
- FAT class approach (1)
- FSW (1)
- Fabricación Aditiva (1)
- Fail-safe design (1)
- Fartigue Strength (1)
- Fast single pulse response (1)
- Fatigue Limit (1)
- Fatigue S-N curve (1)
- Fatigue assessment (1)
- Fatigue crack initiation (1)
- Fatigue crack propagation stages (1)
- Fatigue crack propagation stagesdefects (1)
- Fatigue fracture (1)
- Fatigue lifetime prediction (1)
- Fatigue loading (1)
- Fatigue propagation threshold (1)
- Fatigue strength and life (1)
- Fatigue threshold (1)
- Feinkornbaustähle (1)
- Femtosecond (1)
- Ferngasleitung (1)
- Ferrit (1)
- Ferrite (1)
- Ferritic Alloys (1)
- Ferritic spheroidal (1)
- Ferritic stainless steel (1)
- Ferritic steel (1)
- Ferritic steels (1)
- Ferritic welding electrode (1)
- Ferroelectricity/ferroelectric materials (1)
- Ferromagnetic steels (1)
- Fertigung (1)
- Fertigungstechnologie (1)
- Festigkeit (1)
- Fiber laser (1)
- Filler material (1)
- Filler metal modification (1)
- Filler wire (1)
- Fine-grained Steel (1)
- Finish milling (1)
- Finite Element Analysis (1)
- Finite Element Method (1)
- Finite element (FE) (1)
- Finite element method (FEM) (1)
- Finite-difference time-domain calculations (FDTD) (1)
- Fit4AM (1)
- Flange width (1)
- Flank (1)
- Flaw assessment procedures (1)
- Flaw detection (1)
- Flaw interaction (1)
- Flüssigmetallversprödung (1)
- Force distance curves (1)
- Formation (1)
- Formgedächtnislegierungen (1)
- Forschungsprojekt (1)
- Fracture assessment (1)
- Fracture of weldments (1)
- Frequency domain (1)
- Fresnel reflection (1)
- Fretting (1)
- Fräsbearbeitung (1)
- Fuel Technology (1)
- Functionally Graded Materials (1)
- Funktionally Graded Material (1)
- Fusion Zone (1)
- Fusion welding (1)
- Fusion zone (1)
- Fusion zone profile (1)
- Fusion zone, nickel alloys (1)
- Fügequalität (1)
- Füllgradregelung (1)
- GMAwelding (1)
- GMR (1)
- GMR sensors (1)
- Galvanized steel (1)
- Gap bridging (1)
- Gas analytic (1)
- Gas shielded arc welding (1)
- Gas storage (1)
- Gasdetektion (1)
- Gassensorik (1)
- General analytical solutions (1)
- Gesetz von Archard (1)
- Geteilte Infrastruktur (1)
- Glasspeicher (1)
- Gleeble (1)
- Gleeble testing (1)
- Global stability criterion (1)
- Glow-discharge optical emission spectroscopy (1)
- Gouging (1)
- Gradient-enhanced damage (1)
- Grain growth (1)
- Grain structure (1)
- Graphene oxide (1)
- Graphite cast iron (1)
- Graphite modules (1)
- Graphitentartung (1)
- Grease (1)
- Grease lubrication (1)
- Greens function method (1)
- Gusseisen (1)
- Gusseisen mit Kugelgraphit GJS (1)
- H2 (1)
- H2-Abbau (1)
- H2HohlZug (1)
- H2Hohlzug (1)
- H2safety (1)
- HAZ (1)
- HCF (1)
- HT22 (1)
- Handbook (1)
- Hard metal (1)
- Hard tungsten (1)
- Hard turning (1)
- Hard-turning (1)
- Hastelloy X (1)
- Haynes 282 (1)
- HeLa (1)
- Heat Input (1)
- Heat affected zone (1)
- Heat flow (1)
- Heat generation (1)
- Heat input (1)
- Heat recovery (1)
- Heat saturation function (1)
- Heat source models (1)
- Heating rate (1)
- Heißzug (1)
- Herausforderungen beim Schweißen hochfester FKB (1)
- High Pressure Gaseous Hydrogen (1)
- High Temperature Corrosion (1)
- High brightness (1)
- High power (1)
- High process speeds (1)
- High speed laser cladding (1)
- High strength AlMgSi aluminium alloys (1)
- High strength fine grained structural steels (1)
- High temperature alloys (1)
- High temperature corrosion (1)
- High-Power Welding (1)
- High-entropy alloys (1)
- High-power fibre laser (1)
- High-pressure hydrogen environment (1)
- High-strength (1)
- High-strength fine-grained steels (1)
- High-strength low-alloy steel (1)
- High-strength steel filler metal (1)
- High-strength steel sheets (1)
- Highspeed plasma (1)
- Hochentropiewerkstoff (1)
- Hochfeste Stähle (1)
- Hochfester Feinkornbaustahl S960QL (1)
- Hochfester vergüteter Feinkornbaustahl (1)
- Hochleistungslaserstrahlschweißen (1)
- Hohlprofilknoten (1)
- Hokz-Holz-Kontakte (1)
- Hold time (1)
- Hollow tensile specimen (1)
- Hollow-specimen (1)
- Holz-Holz-Kontakte (1)
- Hot Cracking (1)
- Hot cracking test (1)
- Hot tensile test (1)
- Hot working tool steel (1)
- Humidity (1)
- Hybrid Laser arc Welding (1)
- Hybrid Laser-Arc Welding (1)
- Hybrid part (1)
- Hybrid-laser-arc welding (1)
- Hydraulic reactivity (1)
- Hydrogen Strategy (1)
- Hydrogen Transfer Film (1)
- Hydrogen assisted stress corrosion cracking (1)
- Hydrogen concentration (1)
- Hydrogen degradation (1)
- Hydrogen dependent mechanical properties (1)
- Hydrogen environment (1)
- Hydrogen in metals (1)
- Hydrogen methane (1)
- Hydrogen trapping (1)
- Hydrogen-containing hot gas (1)
- Hydrophobin (1)
- Hydrostatic and arc pressure exceed the Laplace pressure (1)
- I-TRIBOMAT (1)
- I-Träger (1)
- IBESS Approach (1)
- IBESS model for short cracks (1)
- IBESS-Prozedur (1)
- IN 718 (1)
- IN718 PBF-LB/M (1)
- IN725 (1)
- IR-Spektroskopie (1)
- IR-spectroscopy (1)
- Image registration (1)
- Impact Absorbed Energy (1)
- Impact absorbed energy (1)
- Impact damage (1)
- Imperfektion (1)
- Implant failures (1)
- Implant-supported prostheses (1)
- Implant-test (1)
- Implants (1)
- Implementierung (1)
- In situ LIBS (1)
- In situ Monitoring (1)
- In situ measurement, (1)
- In situ measurements (1)
- In-Situ Testing (1)
- In-situ Process Monitoring (1)
- In-situ Prozessüberwachung (1)
- In-situ diffraction (1)
- In-situ tensile test (1)
- In-situ thermography (1)
- In718 (1)
- Inclusion cluster (1)
- Inclusion size (1)
- Inclusions (1)
- Inconel 625 (1)
- Inconel 939 (1)
- Industrial and Manufacturing Engineering (1)
- Infractstructure (1)
- Infrared Thermography (1)
- Initial crack size (1)
- Innovation (1)
- Innovation in OPST facility (1)
- Inserts (1)
- Instumented indentation test (1)
- Integrated alignment features (1)
- Intelligent tribological material characterization (1)
- Intelligente tribologische Werkstoffcharakterisierung (1)
- Inter-layer time (1)
- Interfacial stability (1)
- Intergranular cracking (1)
- Interoperability (1)
- Interrupted milling (1)
- Intrinsic fatigue crack propagation threshold (1)
- Intrinsic fatigue propagation threshold (1)
- Iron (1)
- Iron aluminides (1)
- Iron-based alloys (1)
- J-Integral (1)
- Jacket foundations (1)
- Jacket-Gründungsstrukturen (1)
- Joining (1)
- Joining process (1)
- Joining technology (1)
- Journal (1)
- Kaltriss und Schweißen (1)
- Kaltzähe Stähle (1)
- Karosseriebau (1)
- Keramikfeder (1)
- Kerbschlagbiegeversuch (1)
- Kerbschlagbiegeversuch, Untermaßproben, Normalproben, Skalierung von Ergebnissen (1)
- Kerbspannungskonzept (1)
- Kernel average misorientation (1)
- Keyhole stability (1)
- Keyhole welding (1)
- Kitagawa-Takahashi (K-T) diagram (1)
- Kl (1)
- Knotenweise Zwangsbedingungen (1)
- Kohlenstoffschichten (1)
- Kokillenguss (1)
- Kompetenzzentrum H2Safety@BAM (1)
- Komponenten (1)
- Kontamination von H2 (1)
- Korrosion (1)
- Kriechen (1)
- Kritische Last (1)
- Kryogene Temperatur (1)
- Kurz- und Langriss-Ermüdungsbruchmechanik (1)
- Kurzrissbruchmechanik (1)
- Kurzrisswachstum (1)
- Kurzzeitfestigkeit (1)
- Körperschall (1)
- Künstliche Neuronale Netze (1)
- L-PBF IN718 material (1)
- LA-ICP-SFMS (1)
- LCF region (1)
- LTT filler material (1)
- LTT filler metal (1)
- LTT-Legierung (1)
- LW (1)
- Lab-to-field up-scaling (1)
- Lab-to-field upscaling (1)
- Laboratory X-ray diffraction (1)
- Laboratory experiments (1)
- Lamé curves (1)
- Lamé curves approximation (1)
- Large scale test (1)
- Laser Ablation (1)
- Laser Implantation (1)
- Laser Metal Deposition; Laser Beam Welding; Duplex; Stainless Steel (1)
- Laser Powder Bed Fusion (LPBF) (1)
- Laser Powder Bed Fusion (PBF-LB/M, L-PBF) (1)
- Laser Powder Bed fusion (1)
- Laser Welding (LW) (1)
- Laser cladding (1)
- Laser cutting (1)
- Laser keyhole welding (1)
- Laser melting (1)
- Laser powder-based directed energy deposition (1)
- Laser processing (1)
- Laser surface texturing (1)
- Laser surfacing (1)
- Laser- und Lichtbogenenergie (1)
- Laser-Pulver-Auftragschweißen (LPA) (1)
- Laser-Pulver-Auftragschweißen; Laserstrahlschweißen, Duplex, Pufferschichten (1)
- Laser-based additive manufacturing (1)
- Laser-based powder bed fusion of metal (PBF-LB/M) (1)
- Laser-beam welding, (1)
- Laser-cutting (1)
- Laser-hybrid welding (1)
- Laser-induced oxide layer (1)
- Laser-induced periodic surface strctures (LIPSS) (1)
- Laser-induced periodic surface structures, LIPSS (1)
- Laser-induzierte periodische Oberflächenstrukturen (1)
- Laser-metal-depositon (1)
- Laser-plasma hybrid (1)
- Laserauftragschweißen (1)
- Laserdispergieren (1)
- Laserstrahl-Hybridschweißen (1)
- Laserstrahlhybridschweißen (1)
- Lattice structure (1)
- Lead-free ceramics (1)
- Leckage (1)
- Leichtbauprinzipien (1)
- Life Cycle Assessment (LCA) Fusion welding (1)
- Life Cycle Assessment (LCA) Impact categories (1)
- Life Cycle Assessment (LCA) Schweißprozesse (1)
- Life Cycle Assessment (LCA) Umweltwirkungen (1)
- Life prediction (1)
- Lifetime (1)
- Lifetime normalization (1)
- Ligamentplastifizierung (1)
- Light elements (1)
- Lightweight principles (1)
- Liquid Metal Embrittlement (LME) (1)
- Liquid hydrogen (1)
- Liquid phase sintering (1)
- Local Weld Geometry (1)
- Local critical strain (1)
- Local fatigue spproaches (1)
- Localized Laser Dispersing (1)
- Loch- u. Spaltkorrosion (1)
- Lorentz force (1)
- Lorentz forces (1)
- Low Temperature Toughness (1)
- Low Transformation Temperature (1)
- Low carbon steel (1)
- Low cycle fatigue (1)
- Low feed rates (1)
- Low heat input Gma welding (1)
- Low transformation temperature (1)
- Low transformation temperature filler materials (1)
- Low-Cycle-Fatigue (1)
- Low-cycle fatigue (1)
- L‐PBF (1)
- MAG (1)
- MAG Prozesssteuerung (1)
- MAG-Welding (1)
- MANUFACT (1)
- MIC (1)
- MWIR (1)
- Machinability (1)
- Machine Learning (1)
- Machine learning (1)
- Machine vision (1)
- Magnesium Alloy (1)
- Magnesium alloy (1)
- Magnetic bath support (1)
- Magnetic stray field (1)
- Magnetohydrodynamics (MHD) (1)
- Magnettechnik (1)
- Manufact (1)
- Margin design (1)
- Maritime Components (1)
- Martensit (1)
- Martensitstarttemperatur (1)
- Master Curve Method (1)
- Master curve (1)
- MatCom (1)
- Matching ferritic filler metal (1)
- Material inhomogeneity (1)
- Materialmodellierung (1)
- Materialprüfung (1)
- Materials database (1)
- Materialschaedigung (1)
- Materialschädigung (1)
- Materialuntersuchungen (1)
- Mechanical Properties (1)
- Mechanical anisotropy (1)
- Mechanical properties of the joints (1)
- Mechanical property (1)
- Mechanical-technological properties (1)
- Mechanisch technologische Kennwerte (1)
- Mecánica de Fractura (1)
- Melt pool behaviour (1)
- Melt pool defects (1)
- Melt pool depth (1)
- Melt-pool-monitoring (1)
- Melting (1)
- Messung (1)
- Metal Magnetic Memory (1)
- Metal additive manufacturing (MAM) (1)
- Metal matrix composite (1)
- Metallic components (1)
- Metallic vapour plume (1)
- Metals (1)
- Methan (1)
- Micro computed tomography (1)
- Microalloyed steels (1)
- Microalloying elements Ti and Nb (1)
- Microcracking (1)
- Microfocus X-ray computer tomography (μCT) (1)
- Micromechnical properties (1)
- Microstructure Tensile strength (1)
- Microstructure characterisation (1)
- Microtribology (1)
- Mikro-Computertomographie (1)
- Mikrolegierungselemente (1)
- Mikroorganismen (1)
- Mikrostrukturentwicklung (1)
- Mild steels (1)
- Mini-UAV (1)
- Minimum waiting time (1)
- Mining head gear (1)
- Mis-match (1)
- Misalignment of edges (1)
- Mischverbindung (1)
- Misfit (1)
- Mismatch (1)
- Mittelrippendefekt (1)
- Mixing behavior (1)
- Mobility (1)
- Mock-up (1)
- Model order reduction (1)
- Modeling (1)
- Modelling studies (1)
- Moderate strain rates (1)
- Modified Varestraint Transvarestraint (1)
- Modified Varestraint-/Transvarestraint test (1)
- ModuH2Pipe@BAM (1)
- Molybdenum carbide (1)
- Molybdenum disulphide (1)
- Monitoring von Rohrleitungen (1)
- Monotonic and cyclic crack driving force (1)
- Monte-Carlo simulation (1)
- Morphology control (1)
- Multi - physical modeling (1)
- Multi-materials joining (1)
- Multi-pass welding (1)
- Multi-principal element alloy (1)
- Multielement-Legierung (1)
- Multiple crack initiation (1)
- Multiple crack propagation (1)
- Multiple cracking (1)
- Multiple-principal element alloy (1)
- NIR (1)
- Nachschlagewerk (1)
- Nachwärmung (DHT) (1)
- Nanoadditive (1)
- Nanoparticle (1)
- Nanotribology (1)
- Nanowear (1)
- Narrow gap welding (1)
- Narrow-gap welding (1)
- Natural silver wires (1)
- Near-surface X-ray diffraction (1)
- Near-threshold regime (1)
- Necking (1)
- Neural networks (1)
- Neutron Imaging (1)
- Neutron and X-ray diffraction (1)
- Neutron imaging techniques (1)
- Neutron tomography (1)
- Neutronbeugungsverfahren (1)
- Neutronendiffraktion (1)
- Neutronenradiographie (1)
- Neutronentomographie (1)
- New technologies (1)
- Ni-based austenitic filler metal (1)
- Ni-based austenitic welding electrode (1)
- Ni-based superalloy (1)
- NiTi-Legierungen (1)
- Nickel-based superalloy (1)
- Nickel-based superalloys (1)
- Nickel-iron-alloy (1)
- Nickelbasis-Superlegierungen (1)
- Niobcarbid (1)
- Niobcarbid (NbC) (1)
- Node-release (1)
- Non-destructive Materials (1)
- Non-destructive testing (1)
- Non-sharp defects (1)
- Normalproben (1)
- Normen (1)
- Normung (1)
- Normung Roadmap (1)
- Notched impact strength (1)
- Novel metrology (1)
- Novel optical metrology (1)
- Nuclear reactor systems (1)
- Numerical analysis (1)
- Numerical investigation (1)
- Numerical simulations (1)
- Numerical welding simulation (1)
- Numerical welding simulations (1)
- Numerische ISmulation (1)
- Oberflächenmessung (1)
- Oberflächenmodifikation (1)
- Oberflächenschädigung (1)
- Oberflächenstrukturierung (1)
- Offshore Wind energy (1)
- Offshore steel (1)
- Offshore steels (1)
- Offshore wind turbine (1)
- Offshore wind turbines (1)
- Online monitoring (1)
- Open Data (1)
- Open source (1)
- OpenScience (1)
- Optical Emission Spectroscopy (1)
- Optical emission spectroscopy (1)
- Optical measurement technique (1)
- Optical measurment technique (1)
- Optische Emissionsspektroskopie (1)
- Optische Emissionsspektroskopie (OES) (1)
- Oscillating ball-on-disc test (1)
- Oszillierendes Magnetfeld (1)
- Overview (1)
- Oxide-induced crack closure (1)
- Oxygen pressure surge test (1)
- PAEKs (1)
- PBF/LB (1)
- PCA (1)
- PEAK (1)
- PGD (1)
- PTFE composite (1)
- PTFE composites (1)
- Parabolic flight (1)
- Partial penetration laser hybrid welding (1)
- Partial penetration welding (1)
- Particle erosion (1)
- Particle transfer (1)
- Peak stress method (1)
- Peak stress method (PSM) (1)
- Pearlitic microstructure (1)
- Permeation (1)
- Perspektiven (1)
- Phase analysis (1)
- Phase field method (1)
- Phase field modeling (1)
- Photogrammetry (1)
- Photooxidation (1)
- Physical vapor deposition (PVD) (1)
- Piezoresistive (1)
- Piezoresistive cantilever (1)
- Pipe Welding (1)
- Pipe weld preparation (1)
- Pipeline steel of grade X120 (1)
- Plane crystalization (1)
- Plasma cutting (1)
- Plasma transferred arc welding (1)
- Plasma-cut samples (1)
- Plasma-transferred-arc (1)
- Plastic material flow (1)
- Plume heating (1)
- Poly(acrylic acid) (1)
- Polyethylene (1)
- Polymer (1)
- Polymerkomposite (1)
- Polyurethan (1)
- Pool dimensions (1)
- Pore formation (1)
- Poren (1)
- Porenreduktion (1)
- Porosity reduction (1)
- Porosität (1)
- Post Weld Heat Treatment (PWHT) (1)
- Post processing heat treatment (1)
- Potential drop technique (1)
- Potentiodynamic measurements (1)
- Powder Analysis (1)
- Powder Bed Fusion of Metals with Laser Beams (1)
- Power-to-Gas (1)
- Ppreheating temperature (1)
- Precipitation hardening aluminum alloys (1)
- Precipitation influence (1)
- Preciptiates (1)
- Predicción vida a fatiga (1)
- Preheatin (1)
- Preheating temperature (1)
- Prematurely interrupted tests (1)
- Pressure-dependent solubility (1)
- Prevention (1)
- Primär- und Sekundärspannungen (1)
- Principal Component Analysis (1)
- Principal stress (1)
- Probabilistic Assessment (1)
- Probabilistic assessment (1)
- Probabilistic lifetime prediction (1)
- Probenfertigung (1)
- Probengeometrie (1)
- Probetas miniatura (1)
- Process Chain Integration (1)
- Process Monitoring (1)
- Process Simulation (1)
- Process development (1)
- Processing (1)
- Product standard (1)
- Profilvermessung (1)
- Projekt AGIL - Alterung additiv gefertigter metallischer Materialien und Komponenten (1)
- Projektbegleitender Ausschuss (1)
- Proper generalized decomposition (1)
- Prostheses (1)
- Prozesse (1)
- Prozessregelung (1)
- Prozesssimulation (1)
- Prüfung (1)
- Pulse electric current sintering (1)
- Pulverbettbasiertes Laserstrahlschmelzen (1)
- QI Digital (1)
- Quality Infrastructure (1)
- Quality monitoring (1)
- Quality-X (1)
- Qualität (1)
- Quantitative bioimaging (1)
- R-curve analysis (1)
- Radioactive material (1)
- Radiography (1)
- Radiological inspections (1)
- Rail tracks (1)
- Rainfall simulator (1)
- Rauheit (1)
- Ray teacing (1)
- Ray-tracing methods (1)
- Reactor conditions (1)
- Reciprocating sliding (1)
- Reciprocating sliding wear (1)
- Recomendaciones procedimiento de ensayo (1)
- Recycling (1)
- Reduced Order Model (1)
- Reduced order modelling (1)
- Reference data (1)
- Reference standards (1)
- Refraction (1)
- Regelwerke (1)
- Reibungsreduktion (1)
- Relative humidity (1)
- Reliability (1)
- Renewable Energy, Sustainability and the Environment (1)
- Repair cycles (1)
- Representative Specimens (1)
- Representative material properties (1)
- Repräsentative Werkstoffeigenschaften (1)
- Research and Development (1)
- Residual lifetime (1)
- Residual stress in AM (1)
- Residual stress state (1)
- Resistance Spot Welding (RSW) (1)
- Restlebensdauerprognose (1)
- Retained Austenite (1)
- Ringversuch (1)
- Ripples (1)
- Risikoanalyse (1)
- Risk Assessment (1)
- Riss (1)
- Rissausbreitung (1)
- Rissausbreitungsstadien (1)
- Rissbildung (1)
- Rissfortschrittsdaten (1)
- Rissschließfunktion (1)
- Rissschließphenomen (1)
- Rissspitzenbelastung (1)
- Risswachstum (1)
- Risswiderstand (1)
- Rohrbiegeprüfstand (1)
- Roughness (1)
- Rundnähte (1)
- Runoff (1)
- Röntgenradiographie (1)
- S-N diagram (1)
- S-N probabilistic field (1)
- S-Phase (1)
- S690QL (1)
- SLM printed plasma torch (1)
- SPS (1)
- SS316L alloy (1)
- SWIR (1)
- SWIR thermography (1)
- Safety Assessment (1)
- Sample random results (1)
- Scan strategies (1)
- Scan strategy influence (1)
- Schadenstolerante Bauteilauslegung, (1)
- Schadenstolerante Bauteilauslegung, Restlebensdauer, intrinsischer Schwellenwert gegen Ermüdungsrissausbreitung (1)
- Schadensursachen an Rohrleitungen (1)
- Schallemissionsanalyse (SEA) (1)
- Schallemmission (1)
- Schlichtfräsen (1)
- Schmelzbadstütze (1)
- Schmiermittel (1)
- Schmierstoffe (1)
- Schmierung (1)
- Schutzgas (1)
- Schweißdatenmanagement (1)
- Schweißeigenspannungs-Tiefen-Profile (1)
- Schweißen von kaltzähen Stählen (1)
- Schweißnahtgeometrie (1)
- Schweißprozesse (1)
- Schweißprozessparameter (1)
- Schweißsimulation (1)
- Schweißstruktursimulation (1)
- Schweißtechnik (1)
- Schweißunregelmäßigkeiten (1)
- Schweißverbindung (1)
- Schwer zerspanbare Werkstoffe (1)
- Scratches (1)
- Secondary heat source (1)
- Secondary stresses (1)
- Selective laser beam melting (1)
- Semantic Segmentation (1)
- Sensor (1)
- Sensorik (1)
- Shared infrastruture (1)
- Shielding gas (1)
- Shipbuilding steel (1)
- Short Crack Propagation (1)
- Short crack Propagation (1)
- Short crack propagation (1)
- Shrinkages (1)
- Sicherer Umgang (1)
- Silicon nitride (1)
- SimCoLas (1)
- Single asperity (1)
- Single asperity contact (1)
- Single cell (1)
- Single-pass welding (1)
- Skalierung von Ergebnissen (1)
- Sliding friction (1)
- Slidng wear (1)
- Slow Strain Rate Testing (1)
- Slow strain tensile tests (1)
- Small scale testing (1)
- Snergiedispersive Röntgendiffraktion (1)
- Solidification Cracking (1)
- Solidification behaviour (1)
- Spannung (1)
- Spannungs-Dehnungs-Verhalten (1)
- Spannungsrisskorrosion (1)
- Spark plasma sintering (1)
- Spectroscopy (1)
- Spectrum imaging (1)
- Split Hopkinson bar (1)
- Spreading (1)
- Sprühlichtbogen (1)
- Stabilität von Eigenspannungen (1)
- Stahllegierungen (1)
- Staircase method (1)
- Standard test piece (1)
- Standardization (1)
- Static load (1)
- Statistical analysis (1)
- Statistical distributions (1)
- Statistics (1)
- Statistische Versuchsplanung (1)
- Steady-state weld pool (1)
- Steel and Al (1)
- Steelmaking slag (1)
- Stiffness (1)
- Stift-Scheibe-Anordnung (1)
- Stochastic sample functions (1)
- Strain fields prediction (1)
- Strain rates (1)
- Strain-free lattice references (1)
- Strain-free lattice spacing (1)
- Strain-rate (1)
- Strength mis-match (1)
- Strength mismatch (1)
- Stress Relief Cracking (SRC) (1)
- Stress balance (1)
- Stress balance condition (1)
- Stress relaxation (1)
- Stress-strain behavior (1)
- Stretch-Zone (1)
- Structural integrity assessment procedure (1)
- Structural steel (1)
- Structure analysis (1)
- Study (1)
- Stützeffekte (1)
- Sub-oxide (1)
- Sub-size test piece (1)
- Sulphidation (1)
- Superalloy (1)
- Superconducting magnets (1)
- Supermartensit (1)
- Supermartensitic steel (1)
- Supermatensitischer Stahl (1)
- Support configurations (1)
- Support structures (1)
- Surface Integrity (1)
- Surface cracks (1)
- Surface preparation (1)
- Surface processing (1)
- Surface structures (1)
- Surface temperature (1)
- Surface texture (1)
- Susceptibility (1)
- Synchrotron X-ray diffraction (1)
- Synchrotron diffraction (1)
- Synchrotron radiation (1)
- Synchrotronbeugung (1)
- Systematische Schadensanalysen, Prozeduren (1)
- T24 / 7CrMoVTiB10-10 (1)
- TEKKEN Test (1)
- TEKKEN test (1)
- TEM (1)
- TIG (1)
- TIG-Welding (1)
- TIG-welding (1)
- TaC (1)
- Tantalum carbide (1)
- Technologie (1)
- Technologies (1)
- Temperature distribution determination (1)
- Temperature behavior (1)
- Temperature dependence (1)
- Temperature dependent absorption (1)
- Temperatureinfluss (1)
- Tensile Strength (1)
- Tensile loading (1)
- Tensile resistance spot welding experiment (1)
- Tensile test (1)
- Test procedure (1)
- Test standard (1)
- Testing (1)
- Testing parameters (1)
- Themral cycles (1)
- Thermal analysis (1)
- Thermal conductivity device (1)
- Thermal-desorption spectroscopy (1)
- Thermal-fluid-structure coupling model (1)
- Thermo-fluid dynamics (1)
- Thermodynamic modelling (1)
- Thermodynamic simulation (1)
- Thermodynamische Modellierung (1)
- Thermograhy (1)
- Thermomechanische Eigenschaften (1)
- Thick materials (1)
- Thick plate welding (1)
- Thick plates (1)
- Thick steel plates (1)
- Thick-Walled Steel (1)
- Thick-walled (1)
- Thick-walled Structures (1)
- Thick-walled steels (1)
- Thick-walled structures (1)
- Thin steel plates (1)
- Thoughness (1)
- Three-dimensional crystallization (1)
- Threshold regime (1)
- TiC (1)
- TiN (1)
- Time-of-Flight Mass Spectrometry (1)
- Time-of-Flight secondary ion mass spectrometry (1)
- Titanaluminid (1)
- Titandiborid (1)
- Titanium carbide (1)
- Tomography (1)
- Tool (1)
- Tool service life (1)
- Tool-workpiece interaction (1)
- Toughening mechanisms (1)
- Traglastverhalten (1)
- Transformable steels (1)
- Transient stresses (1)
- Transition temperature (1)
- Tribo-Analytik (1)
- Tribo-analytics (1)
- Tribo-film (1)
- Tribo-tests (1)
- Tribological behavior (1)
- Tribological data (1)
- Tribologische Datenbank (1)
- Tribologsches Charakterisierungsdienste (1)
- Tribometer (1)
- Tribooxidation (1)
- Triobology (1)
- Trockenreibung (1)
- Trägergasheißextraktion (1)
- Tubular joints (1)
- Tubular specimen technique (1)
- Tungsten carbide (WC) (1)
- Turbine components (1)
- Two-dimensional solidification (1)
- Two-run welding technique (1)
- UHMWPE (1)
- UHPFC (1)
- UP Schweißen (1)
- UV radiation (1)
- UV-blocker addition (1)
- Ultra-high strength steel (1)
- Ultraschall-Messtechnik (1)
- Ultraschallunterstützter Fräsprozess (1)
- Ultrasonic Assisted Machining (1)
- Ultrasonic assited machining (1)
- Umweltschutz (1)
- Unterirdische Speicher (1)
- Untermaßproben (1)
- Upscaling (1)
- V-notch impact toughness (1)
- Vakuum (1)
- Vapor recondensation (1)
- Varestraint Test (1)
- Vergüteter hochfester Feinkornbaustahl (1)
- Vernetzte Produktion (1)
- Verschleiß-Map (1)
- Verschleißkoeffizient (1)
- Verschleißreduktion (1)
- Verschleißschutz (1)
- Versetzungsstrukturen (1)
- Verteilte Faseroptische Sensorik (1)
- Verteilten akustischen faseroptischen Sensorik (1)
- Verzug (1)
- Viskosität (1)
- Void defect formation mechanism (1)
- WAAM Ti-6Al-4V (1)
- WC (1)
- WEBAM (1)
- WEZ Aufhärtung (1)
- WIG (1)
- WIG Schweißen (1)
- WRC 92 (1)
- Waiting time (1)
- Warmfeste Stähle (1)
- Warmfester Stahl (1)
- Wasserstoff-Sicherheit (1)
- Wasserstoffbindungsverhalten (1)
- Wasserstoffdiffusion (1)
- Wasserstofferzeugung (1)
- Wasserstoffgradient (1)
- Wasserstoffkonzentration (1)
- Wasserstofflagerung (1)
- Wasserstoffstrategie (1)
- Wasserstoffunterstütze Kaltrissbildung (1)
- Wear mechanism (1)
- Wear mechanisms (1)
- Wear particles (1)
- Wear rate (1)
- Weathering tests (1)
- Weld end crater (1)
- Weld imperfections (1)
- Weld joint (1)
- Weld metal cracking (1)
- Weld pool modeling (1)
- Weld root (1)
- Weld seam geometry (1)
- Weld toe geometry (1)
- Welded joint (1)
- Welding Current (1)
- Welding Simulation (1)
- Welding parameter (1)
- Welding process simulation (1)
- Welding processing influences (1)
- Weldx (1)
- Werkstatt (1)
- Werkstoff (1)
- Werkstoffdatenbank (1)
- Werkstoffkompatibilität (1)
- Werkzeug (1)
- Werkzeugmodifikation (1)
- Werstoff- und geometrische Imperfektion (1)
- Wetting (1)
- White light interferometry (1)
- Widerstandpunktschweißen (1)
- Wind Energy (1)
- Wind turbine (1)
- Windkraftanlagen (1)
- Windturbine (1)
- Windturm (1)
- Wineglass shape (1)
- Wire Electron Beam Additive Manufacturing (1)
- Wire feed laser beam welding (1)
- Wire-based additive manufacturing (1)
- Wärmbehandlung (1)
- Wärmeakkumulation (1)
- Wärmeeinflusszone (1)
- X-ray and neutron diffraction (1)
- X-ray computed tomography (1)
- X-ray computed tomography (XCT) (1)
- X-ray refraction (1)
- X153CrMoV12 (1)
- X8Ni9 (1)
- XRF (1)
- Year in Review (1)
- Zero wear (1)
- Zerspanungswerkzeug (1)
- Zinc (1)
- Zinkbeschichtung (1)
- ZnO films (1)
- ZnO nanorods Nanocrystalline (1)
- Zugversuch (1)
- Zyklische Belastung (1)
- a-C:H (1)
- abtragende Glasbearbeitung (1)
- additive (1)
- additive manufacturing (1)
- arbidic austempered ductile iron (1)
- carrier gas hot extraction (1)
- cold cracking safety (1)
- contact resonance (1)
- contour method (1)
- deposition welding (1)
- digital image correlation (1)
- digitalisation (1)
- dual phase steel (1)
- duplex stainless steel (1)
- fatigue crack growth (1)
- friction (1)
- high-resolution camera (1)
- high-strength steel (1)
- highspeed plasma laser cladding (1)
- hybrid repair (1)
- i-Tribomat (1)
- infrared Thermography (1)
- keyhole dynamics (1)
- laser energy absorption (1)
- laser energy distribution (1)
- laser hybrid welding (1)
- miniature specimens; FCGR curves; intrinsic threshold (1)
- molten pool (1)
- neutron diffraction (1)
- numerical modeling (1)
- pL-droplets (1)
- position detection (1)
- powder bed fusion of metals utilizing a laser beam (1)
- relative Luftfeuchtigkeit (1)
- residual stress analysis (1)
- resistance spot welding (1)
- slip-rolling (1)
- test method (1)
- thermal cycles (1)
- thick plate welding (1)
- tribofilms (1)
- ultraschallunterstütztes Fräsen (1)
- wear (1)
- µ-gravity (1)
- µCT-analysis (1)
- Äquivalente Spannungskonzentrationsfaktoren (1)
- Äquivalente Wärmequelle (1)
- Ökonomische und ökologische Vorteile (1)
- Überblick (1)
- Überwachung von Rohrleitungen (1)
- μCT (1)
- ГИДРОДИНАМИКА (1)
- КОНВЕКЦИЯ (1)
- ЛАЗЕРНАЯ СВАРКА (1)
- МЕТОД КОНЕЧНЫХ ЭЛЕМЕНТОВ (1)
- СВАРОЧНАЯ ВАННА (1)
- ТЕМПЕРАТУРНОЕ ПОЛЕ (1)
- ТЕПЛОПРОВОДНОСТЬ (1)
- ЧИСЛЕННОЕ МОДЕЛИРОВАНИЕ (1)
- кратер шва (1)
- кристаллизация, (1)
- плавление, (1)
- сварочная ванна (1)
- температурное поле (1)
- функция теплонасыщения (1)
Organisationseinheit der BAM
- 9 Komponentensicherheit (1471) (entfernen)
Paper des Monats
- ja (11)
Residual stress formation during repeated gouging and repair welding cycles of high-strength steels
(2024)
The construction of foundation and erection structures for wind power plants requires the use of modern, sustainable and resource-efficient high-strength fine-grained structural steels. Weld defects due to the welding process are unacceptable. To overcome this issue, local thermal gouging followed by re-welding is a common and cost-effective method. The high shrinkage restraint of the gouge by the surrounding structure can cause crack initiation when design and re-weld induced residual stresses are superimposed. This risk is intensified by the progressive degradation of the microstructure and mechanical properties of high-strength steels during the weld repair process.
This investigation focuses on high-strength steels S500MLO for offshore applications and S960QL for mobile crane applications. The reduction and development of residual stresses caused by local thermal gouging and re-welding was investigated. Digital Image Correlated (DIC) stress-strain analysis was performed during preheating, welding and cooling. The results of the global DIC analysis and local longitudinal and transverse residual stresses of the weld determined by X-ray diffraction were found to be in good agreement. Furthermore, different stress levels were identified during gouging and welding. Repeated repair cycles led to an increase of longitudinal and transverse residual stresses in the weld metal as well as a hardness increase in the heat affected zone.
Low Transformation Temperature (LTT)-Schweißzusätze stellen einen innovativen Ansatz zur Erhöhung der Ermüdungsfestigkeit geschweißter Konstruktionen dar. LTT-Schweißzusätze zeichnen sich durch eine martensitische Phasenumwandlung nahe der Raumtemperatur aus, welche Druckeigenspannungen in der Schweißnaht und der Wärmeeinflusszone (WEZ) generieren.
Dieser Vortrag fokussiert sich auf die gezielte Einbringung zusätzlicher LTT-Lagen an ermüdungskritischen Stellen von konventionell geschweißten Verbindungen. Dies ermöglicht eine ökonomische Anwendung, ohne dass die Schweißnahtintegrität zu stark beeinflusst wird. Die Auswirkungen zusätzlicher LTT-Lagen wurden anhand geschweißter Längssteifen aus hochfestem Stahl hinsichtlich der chemischen Zusammensetzung und der Eigenspannungen untersucht. Unter Variation der Schweißgeschwindigkeit und Abstand zur konventionellen Naht konnten 3 unterschiedliche Nahtausführungen des Chrom-Nickellegierten LTT-Zusatzes bewertet werden.
Die chemische Zusammensetzung wurde mittels OES-Analysen untersucht. Dabei stellte heraus, dass die Aufmischung in allen Varianten sehr ähnlich war trotz teils unterschiedlicher LTT-Volumina. Härtebestimmungen ergaben in allen 3 Varianten eine ähnliche Härte. Daraus lässt sich annehmen, dass die Martensitstarttemperatur bei allen Nahtvarianten ähnlich ist.
Röntgenografische Eigenspannungsmessungen belegen, dass die Eigenspannungen am versa-genskritischen Nahtübergang bei Einsatz von LTT-Schweißzusätzen deutlich abgesenkt werden. Während die konventionelle Schweißnaht Zugeigenspannungen von ca. 350 MPa aufweist, können an den LTT-Nähten teilweise Druckeigenspannungen von bis zu -150 MPa nachgewiesen werden. Je höher der Abstand zur konventionellen Naht und je größer das eingebrachte LTT-Volumen ist, umso stärker sind die Eigenspannungsreduzierungen am Nahtübergang. Da in allen 3 Varianten eine ähnliche Martensitstarttemperatur angenommen werden kann, ist somit die Geometrische Komponente der LTT-Zusatzlage ein entscheidender Faktor für die Eigenspannungsreduzierung.
AbstractPowder Bed Fusion with Laser Beam of Metals (PBF-LB/M) has gained more industrial relevance and already demonstrated applications at a small series scale. However, its widespread adoption in various use cases faces challenges due to the absence of interfaces to established Manufacturing Execution Systems (MES) that support customers in the predominantly data-driven quality assurance. Current state-of-the-art PBF-LB/M machines utilize communication architectures, such as OPC Unified Architecture (OPC UA), Message Queuing Telemetry Transport (MQTT) and Representational State Transfer Application Programming Interface (REST API). In the context of the Reference Architecture Model Industry 4.0 (RAMI 4.0) and the Internet of Things (IoT), the assets, particularly the physical PBF-LB/M machines, already have an integration layer implemented to communicate data such as process states or sensor values. Missing is an MES component acting as a communication and information layer. To address this gap, the proposed Extract Transform Load (ETL) pipeline aims to extract relevant data from the fabrication of each build cycle down to the level of scan vectors and additionally to register process signals. The suggested data schema for archiving each build cycle adheres to all terms defined by ISO/TC 261—Additive Manufacturing (AM). In relation to the measurement frequency, all data are reorganized into entities, such as the AM machine, build cycle, part, layer, and scan vector. These scan vectors are stored in a runtime-independent format, including all metadata, to be valid and traceable. The resulting machine log represents a comprehensive documentation of each build cycle, enabling data-driven quality assurance at process level.
In this contribution, we present a physically motivated heat source model for the numerical modeling of laser beam welding processes. Since the calibration of existing heat source models, such as the conic or Goldak model, is difficult, the representation of the heat source using so-called Lamé curves has been established, relying on prior Computational Fluid Dynamics (CFD) simulations.
Lamé curves, which describe the melting isotherm, are used in a subsequent finite-element (FE) simulation to define a moving Dirichlet boundary condition, which prescribes a constant temperature in the melt pool. As an alternative to this approach, we developed a physically motivated heat source model, which prescribes the heat input as a body load directly. The new model also relies on prior CFD simulations to identify the melting isotherm. We demonstrate numerical results of the new heat source model on boundary-value problems from the field of laser beam welding and compare it with the prior CFD simulation and the results of the Lamé curve model and experimental data.
Der Bau von Gründungs- und Turmstrukturen für Windkraftanlagen erfordert den Einsatz moderner, nachhaltiger und ressourcenschonender hochfester Feinkornbaustähle. Durch den Schweißprozess verursachte Schweißnahtfehler sind nicht akzeptabel. Um diese zu beheben, ist das lokale thermische Fugenhobeln mit anschließendem Reparaturschweißen ein gängiges und wirtschaftliches Verfahren. Die hohe Schrumpfbehinderung um die ausgefugte Nut durch das umgebende Gefüge kann zu Rissbildung führen, wenn sich konstruktiv bedingte Spannungen und Eigenspannungen aus der Reparaturschweißung überlagern. Diese Gefahr wird durch die Verschlechterung der Mikrostruktur und der mechanischen Eigenschaften hochfester Stähle während des Schweißreparaturprozesses noch verstärkt.
For the hydrogen-based energy economy of tomorrow, the construction of the necessary infrastructure will play a central role. Most materials used to date, such as welded steels, can be prone to hydrogen embrittlement under certain conditions. This includes the classic delayed cold cracking during welding as well as degradation phenomena during service of components in hydrogen-containing environment. For the evaluation of any hydrogen effect, for example, on the mechanical properties of a welded metallic material, the hydrogen content must be precisely determined. In the case of weld seams, the carrier gas hot extraction (CGHE) according to ISO 3690 is meanwhile state-of-the-art. CGHE is based on accelerated hydrogen degassing due to the thermal activation of hydrogen at elevated temperatures. In addition to the quantification of hydrogen, thermal desorption analysis (TDA) with varying heating rates can be used to determine and evaluate the hydrogen trapping at microstructural defects in the material. For both techniques, experimental and metrological influences must be considered, which have a major effect on the result. For example, ISO 3690 suggests different sample geometries and minimum extraction times for CGHE. This study summarizes the results and experiences of numerous investigations at the Federal Institute for Materials Research and Testing (BAM) with different sample temperatures and geometries (ISO 3690 type B and cylindrical TDA samples) regarding the influence of the sample surface (polished/welded), measurement accuracy depending on the sample volume and the insufficient monitoring of the effect of PI control on the extraction temperature. A deviating extraction temperature from the target temperature can significantly falsify the measurement results. Based on the results, methods are shown which allow the desired extraction temperature to be reached quickly without physically interfering with the measuring equipment. This serves to significantly improve the reliability of the hydrogen measurement through increased signal stability and accelerated hydrogen desorption. In general, an independent temperature measurement with dummy samples is recommended for the heating procedure of choice to exclude possible undesired temperature influences before the measurement. The methods described can be transferred directly to industrial applications
Based on the state-of-the-art research and regulations, the application of the fracture mechanics master curve (MC) concept to ferritic ductile cast iron (DCI) is being investigated in a joint research project between MPA Stuttgart and BAM Berlin. This paper outlines the research approach, the planned investigations and first results of the experimental program.
Dieser Beitrag befasst sich mit der Entwicklung eines wirtschaftlichen und robusten Verfahrens zum Schweißen dicker Stahlbleche. Es werden Ergebnisse für das Fügen von Blechen im Dickenbereich von 25 mm bis 80 mm vorgestellt. Die 30 mm dicken Schweißnähte konnten im Stumpfstoß in zwei Durchgängen unter Verwendung des Laserhybridschweißens und des Unterpulverschweißens (UP) geschweißt werden. Das Laserhybridschweißen wird als Einschweißung mit einer Tiefe von ca. 25 mm ausgeführt. Die UP-Lagen werden auf der gegenüberliegenden Seite des Blechs aufgebracht. Bei richtiger Wahl der Schweißparameter wird der
Nahtquerschnitt durch eine sichere Überlappung beider Lagen geschlossen. Bei Blechdicken über 30 mm ist eine Kantenvorbereitung erforderlich, die eine Ausführung der UP-Fülllagen in Engspalttechnik ermöglicht. Die Vorteile der vorgeschlagenen Prozesskombination liegen darin, dass die Nahtwurzel der Laserhybridnaht nicht geformt werden muss. Defekte in der Wurzel der Laserhybrideinschweißung können durch die UP-Lagen effektiv beseitigt werden. Das Verfahren bietet eine hohe Stabilität des Schweißprozesses in Bezug auf die
Qualität der Blechkanten. Plasmageschnittene Kanten konnten ohne Bindefehler geschweißt werden. Die erreichte Nahtqualität wurde durch zerstörende und zerstörungsfreie Prüfungen bestätigt.
Stresses in repair welding of high-strength steels—part 2: heat control and stress optimization
(2024)
In welding of high-strength steels, e.g. for foundations and erection structures of wind energy plants, unacceptable defects can occasionally be found in the weld area, which should be removed by thermal gouging and subsequent re-welding. High shrinkage restraint of repair welds may lead to crack formation and component failure, predominantly in interaction with degraded microstructures and mechanical properties due to repair cycles. This study aims for elaboration of recommendations for repair concepts appropriate to the stresses and materials involved to avoid cold cracking, damage and expensive reworking. In part 1 [1] of this study, systematic investigations of influences of shrinkage restraint on residual stresses and cold cracking risk during repair welding of two high-strength steels S500MLO for offshore application and S960QL for mobile crane structures were focussed. In this part 2, the microstructure, particularly hardness, and residual stresses due to gouging and influences of heat control parameters in repair welding are analysed. A clear reduction in residual stress after gouging can be observed, especially for the specimens with restrained transverse shrinkage. Gouging to a depth of approx. 2/3 of the seam height does not lead to a complete relaxation of the observed reaction forces. Particularly for the higher strength steel S960QL, there are pronounced areas influenced by the gouging process in which a degradation of the microstructure and properties should be assumed. Overall, the repair welds show a significant increase in the width of the weld and HAZ compared to the original weld, especially in the case of S960QL/G89. The repair welds show higher welding-induced stresses than the original welds, especially in the areas of the HAZ and the base metal close to the weld seam. This behaviour can be attributed overall to increased restraint conditions due to the remaining root weld or shorter gouge grooves. In good agreement with earlier investigations, the residual stresses transverse to the weld can be significantly reduced by upwardly limited working or interpass temperatures, and the reaction stresses resulting from high restraint conditions can be effectively counteracted. The influence of the heat input on the stress formation is low compared to the interpass temperature for both test materials.
The presentation gives an overview of BAM's activities on processing influences and application properties of MPEAs in the form of joined and machined high and medium entropy alloys (CoCrFeMnNi and CoCrNi). In the case of welding, the focus is on defect-free welded joints with sufficient mechanical properties. In the case of machining, the focus is on the possible influence on the surface quality of the materials through adequate milling parameters. In addition, the hydrogen absorption and diffusion properties as well as the electrochemical corrosion behavior are fundamentally examined.
This study investigates the room‐ and high‐temperature (650 °C) tensile and low‐cycle‐fatigue behavior of Inconel 718 produced by laser powder bed fusion (PBF‐LB/M) with a four‐step heat treatment and compares the results to the conventional wrought material. The microstructure after heat treatment is characterized on different length scales. Compared to the wrought variant, the elastic and yield properties are comparable at both test temperatures while tensile strength, ductility, and strain hardening capacity are lower. The fatigue life of the PBF‐LB/M variant at room temperature is slightly lower than that of the wrought material, while at 650 °C, it is vice versa. The cyclic stress response for both material variants is characterized by cyclic softening, which is more pronounced at the higher test temperature. High strain amplitudes (≥0.7%) at room temperature and especially a high testing temperature result in the formation of multiple secondary cracks at the transitions of regions comprising predominantly elongated grain morphology and columns of stacked grains with ripple patterns in the PBF‐LB/M material. This observation and pronounced crack branching and deflection indicate that the cracks are controlled by sharp micromechanical gradients and local crystallite clusters.
Die additive Fertigung mittels Schweißverfahren bietet große ökonomische Vorteile für eine ressourceneffiziente Bauteilherstellung. Offene Fragen bezüglich Homogenität, Anisotropie der Schweißgefüge und den damit verbundenen Bauteileigenschaften stehen einer wirtschaftlichen Verarbeitung oftmals im Wege. Finale Bauteilgeometrie und Oberflächengüte erfordern meist komplementäre subtraktive Fertigungsschritte. Werkstoffe für hochbelastbare Komponenten sind oftmals schwer spanbar. In einem Vorhaben der BAM und des ISAF wurde untersucht, wie die Modifikation der AM-Schweißzusätze und das ultraschallunterstützte Fräsen (US) die Zerspanungssituation verbessern. Der vorliegende Artikel stellt wesentliche Zusammenhänge zwischen Legierung, Gefüge und Zerspanung zweier schwer spanbarer Hochleistungslegierungen (FeNi und CoCr) dar. Großes Potenzial zeigte neben dem US die Modifikation mit Zr und Hf bei Zulegierung in das Schweißgut mittels Beschichtung von Massivdrähten bzw. Herstellung von Fülldrähten.
In this presentation, the results of the determination of the diffraction and single-crystal elastic constants of laser powder bed fused Inconel 718 are presented. The analysis is based on high-energy synchrotron diffraction experiments performed at the Deutsches Elektronen-Synchrotron. It is shown that the characteristic microstructure of laser powder bed fused Inconel 718 impacts the elastic anisotropy and therefore the diffraction and single-crystal elastic constants. Finally, the consequences on the diffraction-based residual stress determination of laser powder bed fused Inconel 718 are discussed.
The present Ph.D. thesis provides a comprehensive experimental and theoretical study of the bulging-cracking relationship in laser beam welding of thick unalloyed steel sheets. It focuses on experimentally proving the existence of the bulging region and on developing a coupled multiphysics mathematical framework to analyze its influence on the three critical factors controlling the susceptibility to solidification cracking, namely the thermal, metallurgical, and mechanical factors.
The research employs a novel experimental setup, utilizing a combination of transparent quartz glass and thick unalloyed steel sheet, enabling real-time visualization of the weld pool geometry and confirming the existence of a distinctive bulging region. To deepen the understanding of these experimental insights, an extensive multiphysics mathematical framework was developed and rigorously verified and validated. This framework introduces an innovative approach using Lamé curves for accurately describing complex three-dimensional weld pool geometries, including the bulging region's characteristics. Through analytical solutions and numerical procedures, it facilitates the computation of solidification parameters, which are crucial for understanding the metallurgical aspects of crack formation. The framework also incorporates a mechanical model to assess and evaluate the local stress distribution within the bulging region.
The findings indicate that an elongated, sharply shaped bulging region significantly increases the susceptibility to solidification cracking. This is attributed to its adverse impact on the distribution and local dwell time of liquid metal residing at grain boundaries during solidification, combined with the localized tensile stresses identified in the bulging region.
In essence, this research contributes to the broader understanding of solidification cracking in laser beam welding of thick unalloyed steel sheets, with a particular focus on the bulging region. The insights and methodologies developed in this thesis are valuable for future research and advancements in the application of the laser beam welding technology for joining high-thickness unalloyed steel components.
Bruchmechanik-basierende Methoden können für die Ermüdungsbewertung von mechanischen Bauteilen angewendet werden, die Defekte oder Risse enthalten und zyklischen Belastungen ausgesetzt sind. Die Kenntnis des Risswachstumsverhaltens für kurze und lange Risse ermöglicht die Bestimmung sowohl endlicher als auch unendlicher Lebensdauer. Ein erstes Problem ergibt sich jedoch aus der empirischen Bestimmung von Ermüdungswerkstoffkennwerten, die je nach Prüfbedingungen, z. B. Prüfmethode, Frequenz und Spannungsverhältnis R, variieren. Dies ist auf die Rissschließeffekte und weitere Umgebungsphänomene zurückzuführen, die das Rissfortschrittsverhalten beeinflussen. Ein zweites Problem ist das Fehlen von Standardversuchsverfahren zur Bestimmung des Schwellenwerts gegen Ermüdungsrissausbreitung ΔKth in Abhängigkeit von der Rissausbreitung. Dies ist problematisch, da ΔKth mit der Zunahme der Rissschließeffekte im Kurzrissbereich zunimmt und seine ungenaue experimentelle Bestimmung zu großen Abweichungen bei der Bewertung und, was noch kritischer ist, zu nicht konservativen Vorhersagen führt. Mit dem Ziel, zuverlässigere und sicherere Bewertungsverfahren bereitzustellen, wird in dieser Arbeit eine Methode vorgeschlagen, die auf effektiven Risswachstumsdaten basiert, die bei hohen Spannungsverhältnissen (R ≈ 0,8) ermittelt wurden. Zur Beschreibung der Entwicklung der Rissschließeffekte wird ein Kurzrissmodell auf der Grundlage von zyklischen R-Kurven und CPLR-Daten verwendet. Die analytischen Vorhersagen werden mit experimentellen Daten verglichen, die zur Validierung des Verfahrens durchgeführt wurden, und die daraus entstandenen Unterschiede werden diskutiert.
Übersetzt mit DeepL.com (kostenlose Version)
In einem laufenden Kooperationsprojekt zwischen der BAM Berlin und der MPA Stuttgart wird das probabilistische Master Curve (MC) Konzept nach ASTM E1921 hinsichtlich seiner Übertragbarkeit auf ferritisches Gusseisen mit Kugelgraphit (DCI) untersucht. Zielsetzung ist die Bereitstellung einer Vorgehensweise zur Bestim-mung und Bewertung der dynamischen Bruchzähigkeit von DCI im Übergangsbe-reich. In diesem Beitrag wird der Versuchswerkstoff der Festigkeitsklasse GJS-400 näher vorgestellt. Ferner werden erste Ergebnisse von zwei bruchmechanischen Versuchsserien an SE(B)140-Großproben bei Belastungsraten von ca. 6∙104 MPa√ms-1 bei -40 °C und 60 °C präsentiert.
Within fracture mechanics safety assessment for steels in nuclear technology, the probabilistic master curve (MC) concept according to ASTM E1921 is currently used for quasi-static loading conditions as a supplement to the established deterministic ASME reference curve concept. However, for ferritic ductile cast iron (DCI), a systematic review of potential modifications to the assumptions and the procedure according to ASTM E1921 and an associated validation are still lacking. For this reason, the application of the fracture mechanics MC concept to ferritic ductile cast iron is being investigated in a joint research project between MPA Stuttgart and BAM Berlin. According to IAEA SSG-26, the safety assessment of DCI containers for transport as well as storage of radioactive materials is based on the fracture mechanics criterion of general crack initiation exclusion. Within this context, the focus of the research project is on brittle fracture. The goal is the establishment of a methodology to determine and assess dynamic fracture toughness values of DCI in the ductile-to-brittle transition regime, using samples extracted from a component.
The experimental program uses a DCI material of grade GJS-400, which is generally used for transport and storage containers of radioactive materials. Firstly, a basic mechanical-technological material characterization will be performed consisting of tensile, Charpy and Pellini tests. Following the material characterization, the loading rate relevant for brittle fracture will be determined using instrumented C(T)25-fracture tests at a temperature of -40°C. To be able to transfer the relevant loading rate to other specimen geometries or sizes, the time-dependent course of the Weibull stress is assessed via numerical analyses. With this information an extensive experimental program consisting of DC(T)9, C(T)25, C(T)50, SE(B)10, SE(B)25 and SE(B)140 specimens is performed. These experimental results will be further supported by numerical and fractographic analyses. The empirical experimental database developed for DCI materials will be used to assess the applicability of the MC concept for DCI materials under dynamic loading.
At the current time manufacturing and precracking of test specimens is ongoing. The authors provide first results concerning the mechanical-technological material characterization, the relevant loading rate for brittle fracture determined via C(T)25 tests, and some early results of other specimen types. These experimental results are also supported by preliminary numerical and statistical analyses.
Erstarrungsrisse bilden sich beim Schweißen hinter dem Schmelzbad. Im verwendeten MAG-Schweißverfahren wurden stark eingespannte Schweißungen mit verschiedenen hochfesten Schweißzusätzen durchgeführt. Alle verwendeten Zusätze weisen unter gewöhnlicher Einspannung keine Tendenz zur Erstarrungsrissbildung auf. In Abhängigkeit der verwendeten Schweißparameter und des Einspanngrades konnten Erstarrungsrisse in den Nähten festgestellt werden. Die Versuche zeigen, dass beim Schweißen hochfester und stark eingespannter Kehlnähte eine Kombination von hohen Wärmeeinträgen und Schweißgeschwindigkeiten zu erhöhter Bildung von Erstarrungsrissen führen kann.
Im Rahmen eines Kooperationsprojekts mit der Schottel GmbH wurde eine bauteilnahe Probengeometrie entwickelt, mit der sich unter Verwendung einer einachsigen Prüfmaschine das Spannungstiefenprofil in dem unter überlagerter Biege- und Zugspannung beanspruchtem Querschnitt im Schweißnahtübergang des Bauteils reproduzieren ließ.
Proben dieser Geometrie wurden vom Kooperationspartner im geschweißten bzw. geschweißten und spannungsarmgeglühten Zustand bereitgestellt. An der BAM wurden je Wärmebehandlungszustand mittels Senkerodieren zwei verschiedene künstliche Defektgeometrien im Schweißnahtübergang eingebracht.
Anhand der Proben wurden experimentell für alle vier Probenzustände Wöhlerlinien für ein Spannungsverhältnis von R = 0,1 ermittelt.
Zusätzlich wurde das u.a. an der BAM entwickelte IBESS-Verfahren angewandt, um die Wöhlerlinien analytisch zu bestimmen. Hierbei wurde eine sehr gute Übereinstimmung von Berechnung und Experiment erreicht, wobei die Berechnung zu einer leicht konservativen Lebensdauervorhersage führte.
Controlled Thermal Severity (CTS) tests are known for applicatying high restraint intensity to fillet welds. Due to two different variations of the test it was possible to apply different amounts of restraint intensity to high-strength GMAW fillet welds at a high level of restraint. The results show the effect of heat input, filler material and restraint intensity on solidification cracking susceptibility.
Die Umstellung der Wirtschaft auf wasserstoffbasierte Energieversorgung soll in Deutschland vor allem auf Basis der Umstellung des bestehenden Erdgasnetzes erfolgen. Dabei sollen ca. 90 % dieser Fernleitungsnetze auf dem bestehenden Erdgasnetz basieren. Die Beimischung von Wasserstoff zum Erdgas als auch der reine Wasserstofftransport werfen jedoch die Frage auf, ob und wie kompatibel die eingesetzten Materialien sind. Die Reparatur- und Erweiterungsfähigkeit von Erdgas-Bestandspipelines ist zu klären, wenn diese auf Wasserstoff umgestellt werden. Denn gerade Gashochdruckleitungen müssen regelmäßig gewartet und erweitert werden, um einen ordnungsgemäßen Betrieb sicherzustellen. Insbesondere das Schweißen unter Betriebsdruck bzw. an in Betrieb befindlichen Gasleitungen ist eine der wichtigsten Instandhaltungstechnologien, unabhängig von der Zusammensetzung des geförderten Mediums. Es ist daher dringend notwendig, eine geeignete Teststrategie zu erarbeiten, welche die nötigen Vorrausetzungen für sicheres Schweißen an in Betrieb befindlichen Druckwasserstoffleitungen schafft und entsprechende Kriterien für die Praxis liefert. Im Projekt H2-SuD - Einfluss des Schweißens auf die Wasserstoffaufnahme und Degradation im Betrieb befindlicher H2-Ferngasleitungen - soll geklärt werden, ob und wie stark mit einer Eigenschaftsdegradation geschweißter Rohrstähle in Gasnetzen in Folge einer Wasserstoffaufnahme zu rechnen ist. Die Präsentation gibt dazu einen kurzen Überblick über den aktuellen Status des Projektes. Die Förderung erfolgt im Rahmen der DVGW-Innovationsprogammes Wasserstoff (Nr. G 202131).
Diese Studie konzentriert sich auf den Einfluss der Bearbeitung auf die Eigenspannungen und den Verzug von WAAM-Proben. Definierte Proben wurden vollautomatisch mit einem speziellen WAAM-Massivdraht (Streckgrenze >820 MPa) mit unterschiedlichen geometrischen Designs geschweißt. Der Eigenspannungszustand vor und nach dem Abtrennen der AM-Struktur von der Substratplatte wurde mittels Röntgenbeugung an der Probenoberfläche analysiert und durch 3D-Verformungsanalysen mittels Photogrammetrie ergänzt. Die Ergebnisse zeigen einen signifikanten Einfluss der Geometrie auf die Relaxation und Umverteilung der Eigenspannungen.
Der Vortrag befasst sich mit der gezielten Einbringung zusätzlicher LTT-Lagen zur Erzeugung von Druckeigenspannungen in ermüdungskritischen Bereichen von konventionellen Schweißverbindungen. Dies ermöglicht eine wirtschaftliche Lösung, ohne die Integrität der Schweißverbindungen zu beeinträchtigen. Dazu wurden Längssteifen aus hochfestem Stahl in der ersten Lage mit konventionellem Schweißzusatzwerkstoff mittels Metall-Lichtbogenschweißen geschweißt. Anschließend wurde ein Chrom-Nickel-legierter LTT-Schweißzusatz auf die Stirnseiten der Steifen aufgebracht. Durch Variation der Schweißparameter konnten verschiedene Schweißnahtgeometrien des LTT-Zusatzwerkstoffs analysiert werden.
The weldability of stainless steels is largely controlled by the chemical composition, and alloys with ferritic or ferritic-austenitic solidification show the highest resistance to hot cracking. As the resulting phase balance also
affects the final properties, it may be beneficial to both foresee and measure the weld metal ferrite content. The WRC ’92 constitution diagram is currently the most accurate prediction tool available, but it does not take the cooling rate into consideration and the precision may be less accurate for stainless steels with high ferrite numbers (FN). This study aims to validate the reliability of the WRC ’92 diagram for weld metals with FN > 50. The chemical composition was altered through gas tungsten arc welding (GTAW) of UNS S32205 with ER347 filler wire that had been PVD-coated with either niobium (Nb), copper (Cu), nickel (Ni), manganese (Mn), carbon (C), or silicon (Si). The actual ferrite content was assessed using image analysis, FERITSCOPE® and X-ray diffraction (XRD). While the WRC ’92 diagram predictions were deemed accurate to acceptable for Ni, Si, and Mn, notable deviations were observed for Nb, Cu, and C. The FeriteScope exhibited a consistent trend with image analysis, though the values were higher, and scatter was wider, and the conversion factor is open for discussion. The lowest accuracy and largest spread were obtained using non-contact XRD, rendering it unsuitable for ferrite measurements of welds.
MVT testing was conducted in Transvarestraint mode in multiple welding conditions and under a range of bending speeds. The materials observed were high strength filler metals used in GTAW namely DIN EN ISO 16834-A G 69 4 M21 Mn3Ni1CrMo (G69), 16834-A G 89 6 M21 Mn4Ni2CrMo (G89 6), 16834-A G 89 5 M21 Mn4Ni2,5CrMo (G89 5) and a filler wire 18276-A T 89 4 ZMn2NiCrMo M M21 1 H5 (T89). For evaluation light optical microscope pictures were used. Pixels containing cracks were manually segmented using a self-written program. Out of the segmented images data including crack length, position and area can be calculated for every crack. The results show dependencies of solidification cracking on the test parameters.
Next to chemical composition, metallurgy and welding parameters, the intensity of restraint is one of the variables influencing solidification cracking. Tests like the Houldcroft Test, rate the hot cracking susceptibility indirectly on the amount of restraint the welding can endure without cracking. Modern lightweight steel construction welds can be subject to a larger amount of restraint due to their high-strength nature compared to classical use cases. By varying the plate thickness of Controlled Thermal Severity (CTS) tests produced out of S1100 QL, it was possible to vary the intensity of restraint on fillet welds at a high level. Testing was conducted with four different filler wires for Metal Active Gas (MAG) welding, including three solid and one metal-cored wire. In addition, two sets of welding parameters were tested. The first set with high heat input and high welding speed was shown to be more prone to solidification cracking compared to the second set with lower heat input and welding speed. The results show an increase in solidification cracking with increasing restraint severity.
Influence of machining on residual stresses in additive manufactured high-strength steel components
(2024)
This study focuses on the effect of machining on the residual stresses and distortion of WAAM specimens. Defined specimens were welded fully automatically with a special WAAM solid wire (yield strength >820 MPa) with different geometric designs. The residual stresses state before and after cutting of the AM structure from the substrate plate were analyzed by means of X-ray diffraction on the specimen surface and complementary by 3d deformation analyses using photogrammetry. The results reveal significant influences of the geometry on the relaxation and redistribution of residual stresses.
This presentation describes the usability of the hollow tensile specimen technique for in-situ material testing in a hydrogen atmosphere.
In addition, the presentation provides an outlook on the methodology for investigating the suitability of pipeline steels and their weld seams for hydrogen operation.
This article focuses on the selective placement of additional LTT layers to generate compressive residual stresses in fatigue-critical areas of conventional weld joints. This enables an economical solution without effecting the integrity of welded joints. For this, longitudinal stiffeners made of high-strength steel were gas metal arc welded using conventional welding consumable in the first layer. Afterwards, a chromium-nickel alloyed LTT welding consumable was deposit on front sides of the stiffeners. By varying the welding parameters, different weld geometries of the LTT filler metal could be analyzed. The effects of additional LTT layers were investigated with regards to residual stresses, microstructure and strength. X-ray residual stresses measurements show that the residual stresses at the failure critical weld toe are significantly reduced by using additional LTT layers. While the conventional weld is characterized by tensile residual stresses, compressive residual stresses can be detected at the LTT weld. The level of residual stresses is influenced by the geometry of the LTT layer. Additional LTT layers with a high offset to the conventional weld generate more compressive residual stress in the HAZ than with a low offset. Therefore, the weld geometry has a considerable impact on the residual stress profile.
Joining and welding technologies are of high importance for the manufacturing of components and parts used in sustainable energy generation, conversion, and transport. In that connection, offshore and on-shore installed wind turbines are of high interest for the generation of electrical energy as well as photo-voltaic systems (solar cells). The electricity can be either directly transported or conversed via power-to-gas e.g., to hydrogen. In that scope, electrolyzer up to MW-range are of interest as well as the conver-sion back to electricity via fuel cells. In addition, hydrogen is a key element of the decarburization of in-dustries as well as the mobility sector encompassing sea, air and land transportation driven by hydrogen or its derivates. Well-known examples cover the direct reduction of iron ore to replace the conventional blast furnace process up to gas turbines or fuel cells for home-end use. All mentioned technologies re-quire reliable components, which are to a high extend dependent on joining and especially welding pro-cessing of materials. Especially, the (petro-) chemical industry has many years of experience with both materials used in hydrogen applications. The challenge is e.g., the transition to mass production of sys-tem components of electrolyzers/fuel cells and for distribution grids. At this point, the scalability of cur-rently applied joining processes often limits the economic efficiency, whereas especially laser welding or additive manufacturing will be of high interest. In that connection, it is very important to provide answers by joint research of universities, institutes, and industrial companies. Very often, solutions are already available and “just” have to be investigated and adapted for the new application, like repair welding of NG pipelines. For that reason, we want to set up a series of comprehensive papers with the aforementioned title. The idea is to get an in-depth but manageable overview of the importance of joining technologies in sustaina-ble energy generation, conversion, and transport encompassing current processes, limitations, and fur-ther perspectives. In that connection, the additive manufacturing is gaining more and more attention. If applicable, current challenges in the adaption or creation of new standards/regulations shall be addressed.
Microalloying elements such as Nb and Ti play a decisive function in achieving the desired mechanical strength of quenched and tempered, high-strength fine-grain structural steels with a nominal yield strength ≥ 690 MPa. The current specifications for the chemical composition only provide manufacturers with upper limits. However, even minor deviations in the alloy concept can have a significant impact on the mechanical properties. Consequently, accurate prediction of weldability and the integrity of welded joints becomes difficult or even impossible due to differences in composition and the resulting microstructures. Undesirable consequences include a possible softening of the heat-affected zone (HAZ) or, conversely, hardening effects. In view of these challenges, various microalloying strategies with different Ti and Nb contents are being systematically investigated for the first time using specially developed laboratory casting alloys. Each alloying route is based on the common S690QL, maintaining both the chemical composition and the heat treatment parameters. To analyse the weldability, three-layer welds were performed using gas metal arc welding (GMAW) and critical microstructures, such as areas of the heat-affected zone (HAZ) that exhibit significant softening or hardening, were identified. The effect of the softened HAZ region on failure was evaluated using transverse tensile specimens. Digital image correlation (DIC) is used to image changes in local strains in different HAZ regions in situ. Using a specially developed mirror system, the local strains of the microstructure zones on the top and bottom of the weld are recorded simultaneously. This makes it possible to analyse how the weld seam geometry (e.g., V-seam) influences the strain gradients. In addition, the analysis of the local deformation helps to understand the effects of the softened HAZ on the global strain, the fracture constriction, the fracture position, and the overall fracture behavior.
As energy carrier of the future, green hydrogen can make a decisive contribution to a sustainable energy supply. Particularly important is the decarbonization of heavy industry. Therefore, a reliable supply of hydrogen must be guaranteed. A hydrogen pipeline grid can achieve this purpose. In Europe concrete plans for a hydrogen pipeline grid already exist, as the so called “European Hydrogen backbone”. As building a completely new pipeline grid is economically not justifiable, a dual-way strategy of repurposing natural gas (NG) pipelines and newly built pipelines is intended. Long distance pipeline grids require regular maintenance and repairs. For natural gas (NG) pipelines in-service welding is state of the art. Concepts such as hot-tapping (drilling into pressurized pipelines) and “stoppling” (sealing off pipeline sections after installing bypasses or pressure relieves) allow the repair of damaged pipeline sections or the installation of new branches without shutting the pipeline down, which in most cases isn’t possible from an economic standpoint. The EIGA 121/14 guideline already pointed out in 2014 that “a hydrogen hot-tap shall not be considered a routine procedure”. This shows that the determination of the transferability of these repair concepts to hydrogen pipelines is of utmost importance. Due to the degrading effects of hydrogen on mechanical proper-ties, commonly referred to as “hydrogen embrittlement” it is necessary to understand and investigate the occurring effects. In the special case of repair welding on in-service hydrogen pipelines an increased hydro-gen uptake due to a large heat input and microstructural changes in the material needs to be considered. Therefore, material degradation must be investigated to determine whether modifications of repair procedures are necessary to ensure a reliable and safe hydrogen transportation via pipelines. For this reason, this paper gives an overview on existing weld repair concepts and its risks and limitations in terms of hydrogen absorption and possible embrittlement effects when transferred to hydrogen pipelines. The complexity lies in a large variety of materials (low alloyed steels), pipeline diameters and corresponding welded joints. The material compatibility of materials in used (repurposed NG-pipelines) and new condition must be investigated. Particularly for repurposed/used pipelines the effect of a pre-matured/corroded inner surface and sometimes insufficient documentation of the material “history” needs to be considered. An overview on ongoing and completed R&D-projects with respect to repair concepts for hydrogen pipelines and hydrogen effects on pipeline materials is given. The focus hereby lies on possible methods of material testing and modeling. Its current difficulties, limits and possible solution will be discussed.
Contemporary steels creep-resistant steels like the 13CrMoV9-10 are used as thick plates e.g., for applications in hydrocrackers. The large plate thickness requires high efficiency welding processes like submerged arc welding (SAW) and a mandatory post weld heat treatment (PWHT). The PWHT-parameters stem from a combination of empirical knowledge and traditional experiments on free shrinking (FS) welds. In that connection, the formation of so-called stress-relief cracking (SRC) must be anticipated. The SRC susceptibility of a welded component is a complex combination and interaction of com-ponent specific, thermal, and metallurgical factors. Many of which have to date not been conclusively researched. For example, it is well known that SRCs develop during PWHT due to formation and growth of carbides on prior austenite grain boundaries, resulting in a significant hardness increase (secondary hardening) and toughness decrease. This leads to a high SRC susceptibility of the coarse grain heat-affected zone (CGHAZ) of the last weld bead during PWHT. This is intensified in case of high residual stresses from the component-specific, structurally induced stiffness. In combination with multi-layer welding this leads to a multiaxial stress distribution. Nonetheless, the combined effect of PWHT and high-residual stresses on the SRC formation is merely unknown. For that reason, this study presents the effect of different heating rates in conjunction with a certain component stiffness. For that reason, SAW joints of 13CrMoV9-10 steel were investigated under FS and defined external restraint condition.
The development of hydrogen technologies entails high safety requirements in distribution and dispensing infrastructure. Therefore, it is necessary to pursue research on material compatibility in hydrogen, especially for critical parts with tribological issues.
The focus of this study is to evaluate the influence of hydrogen on a wider range of commercially available polymer materials. Thereby, the friction and wear behavior of different grades of TPE, POM, PA66, PA12, PPA, PEEK, PPS, PTFE, PAI, PI and PBI were investigated against a rotating steel disk (AISI 304). Filled and unfilled polymers from different suppliers were evaluated at room temperature in air, vacuum and hydrogen gas (H2) as well as in liquid hydrogen at - 253°C (LH2).
The sliding behavior of the polymer materials is discussed by means of surface analyses, whereby special attention is paid to the formation of a transfer film.
According to the results at ambient temperature, the effect of hydrogen environment on the tribological behavior of neat polymers may be related to lack of moisture, but also to saturated hydrocarbons in gaseous hydrogen. In liquid hydrogen, the best tribological performances were achieved with neat PA polymers as well as PPS and PI composites.
Effect of high-pressure hydrogen environment on the physical and mechanical properties of elastomers
(2024)
This study presents the influence of high-pressure hydrogen environment on the physical and mechanical properties of two types of cross-linked hydrogenated acrylonitrile butadiene rubbers. Based on the CSA/ANSI standard, static exposures in hydrogen experiments were performed up to 100 MPa at 120 °C. Characterization before and after exposure was conducted by means of density and hardness measurements, dynamic mechanical analysis (DMA), tensile tests, compression set, FT-IR and AFM analyses to assess effects after decompression. While the effect of high-pressure exposure is significant immediately after exposure, most of the physical and mechanical properties recover after 48 hours. FT-IR, AFM, SEM and compression set results indicate, however, permanent effects.
A fundamental study of physical mechanisms of wineglass-shaped fusion zone profile in laser melting
(2024)
The fusion zone geometry in laser melting processes e.g., laser welding and laser-based additive manufacturing, of metallic materials has commonly a wineglass-shaped profile which is critical to the grain orientation and stress distribution. Hereby, we adopt for the first time a decoupling work through a combination of multi-physics modelling and experiments to reveal the fundamental mechanisms of this special morphology. Two physicsbased easy-to-use metal vapour models are proposed to consider the vapour’s momentum and thermal effects separately. It is found that the direct laser energy absorption and Marangoni shear stress which are widely hypothesised to dominate the wineglass-shape formation show only a minor influence. The additional heating from the metallic vapour plume rather than its momentum impact contributes predominantly to the enlarging of the molten pool top region, resulting directly in the formation of the wineglass-shaped fusion zone. The generality of the plume heating effect is also validated in two types of materials (steel and Al) in a wide range of parameters.
Despite the advances in hardware and software techniques, standard numerical methods fail in providing real-time simulations, especially for complex processes such as additive manufacturing applications. A real-time simulation enables process control through the combination of process monitoring and automated feedback, which increases the flexibility and quality of a process. Typically, before producing a whole additive manufacturing structure, a simplified experiment in the form of a beadon-plate experiment is performed to get a first insight into the process and to set parameters suitably. In this work, a reduced order model for the transient thermal problem of the bead-on-plate weld simulation is developed, allowing an efficient model calibration and control of the process. The proposed approach applies the proper generalized decomposition (PGD) method, a popular model order reduction technique, to decrease the computational effort of each model evaluation required multiple times in parameter estimation, control, and optimization. The welding torch is modeled by a moving heat source, which leads to difficulties separating space and time, a key ingredient in PGD simulations. A novel approach for separating space and time is applied and extended to 3D problems allowing the derivation of an efficient separated representation of the temperature.
The results are verified against a standard finite element model showing excellent agreement. The reduced order model is also leveraged in a Bayesian model parameter estimation setup, speeding up calibrations and ultimately leading to an optimized real-time simulation approach for welding experiment using synthetic as well as real measurement data.
It is proposed to model the experimentally observed weld pool boundary with superellipses (Lamé curves) and to find the unknown parameters of the curves using optimization methods. It has been shown experimentally that during laser welding of austenitic stainless steel with a thickness of 2 mm at a speed of 20 mm/s, the rear weld pool part has a shape close to triangular which can be accurately approximated by a superellipse. Analytical dependences of the trajectory and growth rate of the crystal and its cross-sectional area on the geometry of the rear weld pool part are obtained.
A method of solving the thermo-fluid dynamics problem is presented, enabling the prediction of the shape and dimensions of the weld pool during keyhole laser welding of thick plates. It is shown that the rear weld pool boundary can be satisfactorily approximated by a set of superellipses (Lamé curves). The presence of a convex rear weld pool boundary in the mid-plane has been observed experimentally and reproduced numerically. It was shown that in this zone the concentration of liquating impurities increases and the local solidification temperature decreases, contributing to the susceptibility to hot cracking.
Hydrogen has great potential on the path towards decarbonization of the energy and transport sectors and can mitigate the urgent issue of global warming. It can be sustainably produced through water electrolysis with potentially zero emissions, and efficiently used (e.g., in fuel cell systems). Despite its environmental advantages, hydrogen-metal interactions could result in the degradation of the mechanical properties of several structural materials. In order to determine the magnitude of the material degradation in relation to hydrogen exposure, extensive material testing is required. The standardized procedure for in-situ testing for the quantification of the impact of compressed gaseous hydrogen (CGH2) relies on the utilization of an autoclave around the tested specimen. Such test set-up is complex, expensive, time-consuming and requires special equipment, trained personnel, and strict safety procedures. A relatively recent method to circumvent these issues and provide affordable results consists of using hollow specimens, thus applying the hydrogen pressure inside rather than outside the specimen. It allows to reduce the volume of hydrogen by several orders of magnitude and to perform the tests more efficiently and in a safer manner. This study focuses on evaluating the tensile properties of X65 vintage pipeline steel tested in a high-pressure hydrogen environment using hollow specimens. Tests are performed in 6 MPa H2 and Ar at the nominal strain rate of 10−6 s−1 to evaluate the reduced area at fracture and the elongation loss. The effect of surface finishing on crack initiation and propagation is investigated by comparing two different manufacturing techniques. In this way, this study provides insights into the applicability of a novel, reliable, and safe testing method which can be used to assess the hydrogen-assisted ductility loss in metallic materials.
Multiple principal element alloys encompass the well-known high entropy alloys (HEA). The alloy system represents a new class of materials consisting of at least three alloying elements, each containing 5 to 35 at.%. Thus, this alloying concept differs fundamentally from conventional materials such as steel or nickel alloys. For this purpose, the alloying elements are specifically selected, the microstructures are adjusted in a single-phase and, in some cases, multi-phase manner. In particular, conflicting goals, such as the trade-off between strength and ductility in conventional steels, are overcome. However, in the last 20 years, the focus has been on material synthesis. With the increase in available material quantities, the focus is now on processing issues such as joining and welding processes. The weldability of HEAs has received very little attention so far. The experience with dissimilar metal welds is completely lacking but is essential for the application of these materials in combination with conventional materials. The present study presents comprehensive experimental results on the weldability of an equimolar CoCrFeMnNi-HEA in cold-rolled and heat-treated condition, which was joined by tungsten inert gas welding to an austenitic steel AISI 304. The mechanical properties of the dissimilar metal welds were characterized by cross-weld tensile samples, whereas the local deformation in the weld of the different welding zones was measured by digital image correlation. In accordance with the respective initial HEA condition (cold-rolled vs. heat-treated), the local strain behavior was divergent and influenced the global mechanical properties of both DMW types. Nonetheless, the experiments provided proof in principle of the weldability for dissimilar joints of the CoCrFeMnNi-HEA welded to conventional materials like austenitic stainless steels ensuring a corresponding capability for mechanical loading. This allows further considerations on the application of these innovative materials.
The hydrogen economy is one of the main solutions for achieving climate neutrality in Europe. Metallic materials, predominantly steels, are the most common structural materials in the various components along the hydrogen supply chain. Ensuring their sustainable and safe use in hydrogen technologies is a key factor in the ramp-up of the hydrogen economy. This requires extensive materials qualification, however, most of the accepted, and standardised test methods for determining the influence of gaseous hydrogen on metallic materials describe complex and costly procedures that are only available to a very limited extent worldwide (e.g., autoclave technique).
The hollow specimen technique is presented as an alternative method that can overcome the limitations of current techniques and complement them. To standardise the technique, a process has been initiated by ISO in 2021. Knowledge gaps for tests with the technique in hydrogen have been identified by DIN. The H2HohlZug project, which falls under the umbrella of TransHyDE, aims to address the identified knowledge gaps and provide a foundation for a comprehensive standardisation of the hollow specimen technique.
Die Erzeugung rissschließfreier Anrisse in gekerbten bruchmechanischen Proben für anschließende Ermüdungsversuche kann durch eine zyklische Druckbelastung an der Kerbe erfolgen: Bei der Erstbelastung wird eine plastische Verformung an der Kerbspitze erzeugt, welche Zugeigenspannungen und damit eine risstreibende Kraft bei der folgenden zyklischen Druckbelastung hervorruft. Durch das Risswachstum kommt es zu einer Entspannung, bis der Riss schließlich arretiert, weil die effektive risstreibende Kraft auf den Schwellenwert abgesunken ist. Um Kurzrisswachstum in additiv, mittels pulverbettbasiertem Laserstrahlschmelzen (Laser Powder Bed Fusion - LPBF) gefertigtem AISI 316L Stahl und seinem konventionell erzeugten, warmgewalzten Pendant zu untersuchen, wurde dieses Verfahren im Rahmen der vorliegenden Arbeit genutzt. Im Falle des additiv gefertigten Materials kam es zu unerwartet langem Ermüdungsrisswachstum, bevor der Riss arretierte. Zur Ermittlung der Ursache erfolgte eine Messung der Eigenspannungsverteilungen mittels Neutronendiffraktion in der Kerbebene der additiv gefertigten Proben. Anschließend wurde ein Finite-Elemente-Modell zur Simulation des Ermüdungsrisswachstums in konventionellem und additiv gefertigtem Material implementiert. Im Rahmen dieses Vortrages wird insbesondere auf das Vorgehen bei der Simulation und auf die getroffenen Annahmen und Vereinfachungen eingegangen. Die Resultate werden mit den experimentellen Ergebnissen verglichen und das für die Simulation von Risswachstum genutzte Knoten-Freigabe-Verfahren (Node-Release), das Einbringen von Eigenspannungen als initiale Spannungen in der Simulation, und die Rechengrößen zur Quantifizierung der risstreibenden Kraft kritisch diskutiert.
Offshore wind energy plays an important role for the desired transition towards a carbon dioxide free industry within the next decades. However, the grounding of the offshore wind plants governs the overall installation process besides bureaucratic bottlenecks.
The application of lightweight principles in steel construction, e.g. the usage dissolved load-bearing structures, so called Jackets foundations, offer great potential in reducing the resource consumption, especially with respect to the needed amount of steel.
In this context this paper focuses on a fully digitalization of the welding manufacturing and as well as testing chain to enable a fully automated manufacturing as well as quality assessment of tubular nodes as key element of Jackets foundation structures. Furthermore, the relationship between the seam shape geometry and resulting fatigue strength is evaluated by numerical methods incorporating bionic principles. It is shown that tubular nodes can be welded fully automatically taking geometry tolerances into account. Moreover, the seam shape could be manufactured as requested by the numerical models which offers great potential for an extended lifetime. Subsequently, the improvements in resource efficiency and reduction of carbon dioxide emissions are evaluated by a life-cycle-assessment.
Direct energy deposition additive manufacturing technologies utilizing an electric arc offer a great potential in generating large volume metal components. However, the selection of process parameters that yield the desired near net shape design as well as the requested mechanical component behavior is not a trivial task due to the complex relationship. Exemplarily for additive manufacturing of high-strength precipitation hardening AlMgSi-aluminum alloy this paper shows the application of a newly developed matching solid welding wire doped with TiB as grain refiner. The correlation between process parameters and component quality is examined analyzing the size and distribution of pores as well as the grain morphology. Furthermore, the influences of different post-weld heat treatments are evaluated to meet the reference mechanical properties of the corresponding wrought material. Finally, the digital integration of the entire additive manufacturing chain enables an overall traceability of the relevant process steps which is the basis for a reliable subsequent quality assessment.