Ingenieurwissenschaften und zugeordnete Tätigkeiten
Filtern
Dokumenttyp
- Vortrag (63)
- Zeitschriftenartikel (34)
- Beitrag zu einem Tagungsband (21)
- Posterpräsentation (7)
- Forschungsdatensatz (3)
Sprache
- Englisch (99)
- Deutsch (28)
- Mehrsprachig (1)
Schlagworte
- Additive manufacturing (25)
- Laser powder bed fusion (24)
- Additive Manufacturing (22)
- Additive Fertigung (16)
- Thermography (12)
- Laser Powder Bed Fusion (8)
- Inconel 718 (7)
- Laser beam welding (7)
- AISI 316L (6)
- AlSi10Mg (6)
- Digitalisierung (6)
- Electromagnetic forces (6)
- Heat accumulation (6)
- Infrared thermography (6)
- Joining dissimilar materials (6)
- PBF-LB/M (6)
- Steel and aluminium (6)
- AGIL (5)
- Additive manufacturing (AM) (4)
- Elastic modulus (4)
- Fatigue (4)
- L-PBF (4)
- Position detection (4)
- Qualitätsinfrastruktur (4)
- Qualitätssicherung (4)
- Residual Stress (4)
- Selective Laser Melting (SLM) (4)
- Shear modulus (4)
- Tensile properties (4)
- Young's modulus (4)
- Ageing (3)
- Bruchmechanik (3)
- Chunky graphite (3)
- Cold Spray (3)
- Diffraction (3)
- Digitalisation (3)
- FEM (3)
- Heat treatment (3)
- Hot stamping (3)
- Hybrid repair (3)
- In situ monitoring (3)
- In-situ monitoring (3)
- In-situ process monitoring (3)
- Inter layer time (3)
- Laser Welding (3)
- Laser implantation (3)
- Microstructure (3)
- Quality Assurance (3)
- Reproducibility (3)
- Selective laser melting (SLM) (3)
- (U)HMWPE (2)
- Analytisches Modell (2)
- Bauteilbewertung (2)
- Bead-on-plate welds (2)
- Build direction (2)
- Build-up Orientation (2)
- Computed Tomography (2)
- Computed tomography (2)
- Copper powder particles (2)
- Creep (2)
- Defects (2)
- Ductile cast iron (2)
- Dynamische Beanspruchung (2)
- Electrical conductivity (2)
- Electron backscatter diffraction (2)
- Fail-safe (2)
- Fatigue properties (2)
- Ferritic spheroidal graphite cast iron (2)
- Fracture (2)
- Fracture resistance (2)
- Fracture toughness (2)
- Frequenzanalyse (2)
- General Materials Science (2)
- Gusseisen mit Kugelgraphit (2)
- Heat treatments (2)
- High-resolution camera (2)
- Hohlzugprobe (2)
- Hybrid Part (2)
- Hybrid components (2)
- Image processing (2)
- In-situ Monitoring (2)
- Irradiation (2)
- Keyhole porosity (2)
- Laboratory specimens (2)
- Large electrical high-voltage machine (2)
- Laser Powder Bed Fusion (L-PBF) (2)
- Laser beam melting (LBM) (2)
- Laser welding (2)
- Liquation Cracking (2)
- Master Curve-Konzept (2)
- Mechanical Engineering (2)
- Mechanical behavior (2)
- Mechanics of Materials (2)
- Neutron diffraction (2)
- PBF-LB/M/316L (2)
- PBF/LB-M (2)
- Pre-weld Preparation (2)
- Process monitoring (2)
- Process parameter optimization (2)
- Quantification (2)
- Recognition (2)
- Representative specimens (2)
- Residual stress (2)
- Rissbildung in Stahl (2)
- Round robin (2)
- SHPB (2)
- SWIR camera (2)
- Schallemission (2)
- Stainless Steel (2)
- Structure (2)
- Surface modification (2)
- Surface structuring (2)
- Tensile performance (2)
- Thermal history (2)
- Thermografie (2)
- Ti-6Al-4V (2)
- WAXD (2)
- Wasserstoff (2)
- X-ray and Neutron Diffraction (2)
- 316L (1)
- Absorbed energy (1)
- Accoustic emission (1)
- Acoustic emission (1)
- Additive Manufacturing (AM) (1)
- Additive surface treatment (1)
- Adiabatic shear bands (1)
- Artungleiche Werkstoffe (1)
- Bainitischer Schmiedestahl (1)
- Bauteilauslegung (1)
- Betriebsfestigkeit (1)
- Bridging voids (1)
- Camera (1)
- Cellular substructure (1)
- Characterization (1)
- Charpy Impact Test (1)
- Charpy Transition Curve (1)
- Charpy pendulum impact test (1)
- Chunky graphite degeneration (1)
- Chunky-Graphit (1)
- Component assessment (1)
- Computer Aided Manufacturing (1)
- Condensed Matter Physics (1)
- Constraint (1)
- Conversion of results (1)
- Convolutional Neural Networks (1)
- Convolutional neural networks (CNN) (1)
- Correlation microstructure to properties (1)
- Crack (1)
- Creep behavior (1)
- Curve fitting (1)
- Cyclic stress-strain curve (1)
- Damage tolerance (1)
- Data Integrity (1)
- Data-driven quality assurance (1)
- Defect detection (1)
- Defect prediction (1)
- Defekte (1)
- Design for Additive Manufacturing (DfAM) (1)
- Diffraction Elastic Constants (1)
- Digital Twin (1)
- Digital image correlation (1)
- Digitale Qualitätssicherung (1)
- Direct Energy Deposition (1)
- Ductile Cast Iron (1)
- Duktiles Gusseisen (1)
- Dynamic Fracture Toughness (1)
- Dynamic fracture toughness (1)
- Eigenspannung (1)
- Electron backscattered diffraction (1)
- Elektromagnetische Schmelzbadbeeinflussung (1)
- Entwicklung (1)
- FAIR data (1)
- Fail-safe design (1)
- Fatigue Crack Growth (1)
- Fatigue crack propagation (1)
- Fatigue crack propagation threshold (1)
- Fatigue damage (1)
- Fatigue loading (1)
- Ferritic spheroidal (1)
- Finite element analysis (1)
- Finite element method (1)
- Flaw detection (1)
- Formation (1)
- Fracture assessment (1)
- Frequency domain (1)
- Friction (1)
- Fügetechnologie (1)
- Gradient-enhanced damage (1)
- Graphite cast iron (1)
- Graphitentartung (1)
- Gusseisen mit Kugelgraphit GJS (1)
- H2Safety@BAM (1)
- Haynes 282 (1)
- Heat Treatment (1)
- Heat affected zone (1)
- High temperature alloys (1)
- High-pressure (1)
- Hollow tensile specimen (1)
- Hybrid part (1)
- Hydrogen (1)
- IN 718 (1)
- IN718 (1)
- Image registration (1)
- In situ Monitoring (1)
- In-Situ Testing (1)
- In-situ Prozessüberwachung (1)
- In-situ thermography (1)
- Inter-layer time (1)
- L-PBF 316L (1)
- LPBF (1)
- LW (1)
- Laser Implantation (1)
- Laser Powder Bed Fusion (LPBF) (1)
- Laser Powder Bed Fusion (PBF-LB/M) (1)
- Laser Powder Bed Fusion (PBF-LB/M, L-PBF) (1)
- Laser Powder Bed fusion (1)
- Laser Welding (LW) (1)
- Laser dispersing (1)
- Laser powder bed fusion (L-PBF) (1)
- Laser-based powder bed fusion of metal (PBF-LB/M) (1)
- Laserimplantation (1)
- Laserstrahlschmelzen (1)
- Laserstrahlschweißen (1)
- Lattice structure (1)
- Lorentz forces (1)
- Low-cycle fatigue (1)
- L‐PBF (1)
- Machine Learning (1)
- Machine learning (1)
- Machine vision (1)
- Master Curve (1)
- Master Curve Method (1)
- MatCom (1)
- Mechanical properties (1)
- Mechanische Eigenschaften (1)
- Melt-pool-monitoring (1)
- Mikrostruktur (1)
- ModuH2Pipe@BAM (1)
- Online monitoring (1)
- Optical Tomography (1)
- Optical tomography (1)
- Pore formation (1)
- Potential drop technique (1)
- Preheating temperature (1)
- Presshärten (1)
- Prevention (1)
- Principal stress (1)
- Process Chain Integration (1)
- Process Monitoring (1)
- Process Simulation (1)
- Product standard (1)
- Properties (1)
- QI Digital (1)
- Quality-X (1)
- Reference data (1)
- Reliability (1)
- Repair (1)
- Repair of gas turbine blades (1)
- Representative Specimens (1)
- Residual stresses (1)
- SLM (1)
- SWIR thermography (1)
- Seam geometry (1)
- Selective Laser Melting (1)
- Sicherheit (1)
- Simulation (1)
- Slow Strain Rate Testing (1)
- Split Hopkinson bar (1)
- Stahl und Aluminium (1)
- Standard test piece (1)
- Steel (1)
- Stiffness (1)
- Structural integrity assessment procedure (1)
- Sub-size test piece (1)
- Supportless (1)
- Surface temperature (1)
- Temperature dependence (1)
- Tensile strength (1)
- Tensile testing (1)
- Test standard (1)
- Testing (1)
- Texture (1)
- Thermograhy (1)
- Tool steel (1)
- Transition temperature (1)
- Tribologie (1)
- Triobology (1)
- Viscoplasticity (1)
- Wear (1)
- Weld geometry (1)
- Werkzeugmodifikation (1)
- Wärmeakkumulation (1)
- X-ray Diffraction (1)
- X-ray computed tomography (XCT) (1)
- X-ray diffraction (1)
- Zwischenlagenzeit (1)
- additive manufacturing (1)
- high-resolution camera (1)
- hybrid repair (1)
- infrared Thermography (1)
- position detection (1)
- powder bed fusion of metals utilizing a laser beam (1)
- Überblick (1)
Organisationseinheit der BAM
- 9.6 Additive Fertigung metallischer Komponenten (128) (entfernen)
Eingeladener Vortrag
- nein (63)
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.
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.
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.
A steel pipeline segment of 2.5 m length was subjected to quasi-static four-point bending load in three steps for studying the initial cracking and damage accumulation based on the Acoustic Emission (AE) technique and by the direct current potential drop (DCPD) technique. For the latter, a new post-test analysis method was established.
AE is found more sensitive to crack initiation than DCPD. Formation of mesoscopic and macroscopic cracks as well as their closure and the resulting friction generate weighted peak frequencies below 400 kHz, whereas microscopic cracking produces AE with broad band spectra identifiable by weighted peak frequencies above 400 kHz. Critical states alike the maximum load level and the leak opening were accompanied by peak amplitudes above 85 dBAE. This rather fundamental study provides a data base for possibly developing advanced strategies of detection and alarm systems based on acoustic monitoring of pipelines, or at least, steel structures.
Since there is a continuously growing demand for complex, frequently heavy-sectioned spheroidal graphite cast iron (SGI) castings it is worth paying attention to the chunky graphite (CHG) degeneration which may occur under certain technological circumstances. Although a reference line for preventive actions in terms of general metallurgical and process measures could be drawn to avoid CHG in heavy-sectioned ferritic SGI castings, a broad majority of experts claim the avoidance of CHG in heavy sections cannot yet be rated a hundred percent process safe. A major reason may be seen in the fact that a universal, generally accepted explanation of CHG formation and growth has not yet been established, although several theories have been proposed. Nevertheless, metallurgical aspects are not in the focus of this paper.
This paper is about the current state of methods to detect CHG in SGI on the laboratory and component scales. Capabilities and limits of different metallographic, fractographic and non-destructive computer tomographic methods to recognize and quantify CHG are discussed. With respect to the characteristic fili-gree three-dimensional string-like, multi-branched CHG structure, which is non-isometric and non-dispersed, serious implications on the possibility to quantitatively characterize the amount of CHG must be considered.
In contrary to the metallurgical aspects, the knowledge about the impact of CHG on the materials and com-ponents properties is still surprisingly limited. Therefore, special emphasis of this paper is on the impact of CHG degeneration on the properties of ferritic SGI. Experimental results are reviewed to illustrate the effect of CHG on mechanical strength and ductility properties as well as fracture mechanics properties in terms of crack resistance and fracture toughness.
The present situation is characterized by discussions and uncertainty about the acceptance or rejection of SGI components containing CHG. Addressing this, conclusions from the materials engineering point of view are drawn for quality control, a safe operational strategy in the foundry and component safety.
Since there is a continuously growing demand for complex, frequently heavy-sectioned spheroidal graphite cast iron (SGI) castings it is worth paying attention to the chunky graphite (CHG) degeneration which may occur under certain technological circumstances. Although a reference line for preventive actions in terms of general metallurgical and process measures could be drawn to avoid CHG in heavy-sectioned ferritic SGI castings, a broad majority of experts claim the avoidance of CHG in heavy sections cannot yet be rated a hundred percent process safe. A major reason may be seen in the fact that a universal, generally accepted explanation of CHG formation and growth has not yet been established, although several theories have been proposed. Nevertheless, metallurgical aspects are not in the focus of this paper.
This paper is about the current state of methods to detect CHG in SGI on the laboratory and component scales. Capabilities and limits of different metallographic, fractographic and non-destructive computer tomographic methods to recognize and quantify CHG are discussed. With respect to the characteristic fili-gree three-dimensional string-like, multi-branched CHG structure, which is non-isometric and non-dispersed, serious implications on the possibility to quantitatively characterize the amount of CHG must be considered.
In contrary to the metallurgical aspects, the knowledge about the impact of CHG on the materials and com-ponents properties is still surprisingly limited. Therefore, special emphasis of this paper is on the impact of CHG degeneration on the properties of ferritic SGI. Experimental results are reviewed to illustrate the effect of CHG on mechanical strength and ductility properties as well as fracture mechanics properties in terms of crack resistance and fracture toughness.
The present situation is characterized by discussions and uncertainty about the acceptance or rejection of SGI components containing CHG. Addressing this, conclusions from the materials engineering point of view are drawn for quality control, a safe operational strategy in the foundry and component safety.
The elastic properties (Young's modulus, shear modulus) of Ni-based alloy Inconel IN718 were investigated between room temperature and 800 °C in an additively manufactured variant (laser powder bed fusion, PBF‑LB/M) and from a conventional process route (hot rolled bar). The moduli were determined using the dynamic resonance method. The data set includes information on processing parameters, heat treatments, grain size, specimen dimensions and weight, Young’s and shear modulus as well as their measurement uncertainty.
The dataset was generated in an accredited testing lab using calibrated measuring equipment. The calibrations meet the requirements of the test procedure and are metrologically traceable. The dataset was audited as BAM reference data.
The elastic properties (Young's modulus, shear modulus) of austenitic stainless steel AISI 316L were investigated between room temperature and 900 °C in an additively manufactured variant (laser powder bed fusion, PBF‑LB/M) and from a conventional process route (hot rolled sheet). The moduli were determined using the dynamic resonance method. The data set includes information on processing parameters, heat treatments, grain size, specimen dimensions and weight, Young’s and shear modulus as well as their measurement uncertainty.
The dataset was generated in an accredited testing lab using calibrated measuring equipment. The calibrations meet the requirements of the test procedure and are metrologically traceable. The dataset was audited as BAM reference data.
This article reports temperature-dependent elastic properties (Young’s modulus, shear modulus) of three alloys measured by the dynamic resonance method. The alloys Ti-6Al-4V, Inconel IN718, and AISI 316 L were each investigated in a variant produced by an additive manufacturing processing route and by a conventional manufacturing processing route. The datasets include information on processing routes and parameters, heat treatments, grain size, specimen dimensions, and weight, as well as Young’s and shear modulus along with their measurement uncertainty. The process routes and methods are described in detail. The datasets were generated in an accredited testing lab, audited as BAM reference data, and are hosted in the open data repository Zenodo. Possible data usages include the verification of the correctness of the test setup via Young’s modulus comparison in low-cycle fatigue (LCF) or thermo-mechanical fatigue (TMF) testing campaigns, the design auf VHCF specimens and the use as input data for simulation purposes.
State-of-the-art laser powder bed fusion (PBF-LB/M) machines allow pre-heating of the substrate plate to reduce stress and improve part quality. However, two major issues have been shown in the past: First, with increasing build height the apparent pre-heat temperature at the surface can deviate drastically from the nominal pre-heat temperature in the substrate plate. Second, even within a single layer the local surface pre-heat temperature can show large gradients due to thermal bottlenecks in the part geometry underneath the top surface. Both lead to unwanted changes in microstructure or defects in the final parts. In this study, a first attempt is taken to show the feasibility of pre-heating the top surface with the onboard laser beam to overcome the mentioned issues. A single layer of a group of three parts built from IN718 to a height of 33.5 mm is pre-heated in a commercially available PBF-LB/M machine to an average steady state surface temperature of 200 °C using the onboard laser beam. The parts are continuously heated, omitting powder deposition and melting step. Temperatures are measured by thermocouples underneath the surface. The experiments are supported by a thermal finite element (FE) model that predicts the temperature field in the parts. When heating the parts uniformly with the laser beam, differences in surface temperatures as large as 170 K are observed. To overcome this inhomogeneity, the heat flux supplied by the laser beam is modulated. An optimized, spatial heat flow distribution is provided by the thermal FE model and translated into a scan pattern that reproduces the optimized heat distribution on the PBF-LB/M machine by locally modulating hatch distance and scan velocity. This successfully reduces the differences in surface temperature to 20 K. Thermographic imaging shows that a homogeneous surface temperature can be achieved despite the localized heat input by the beam. The potential for industrial application of the optimized laser-heating technique is discussed.