Filtern
Erscheinungsjahr
Dokumenttyp
Sprache
- Englisch (47)
- Mehrsprachig (2)
Referierte Publikation
- ja (49) (entfernen)
Schlagworte
- Microstructure (8)
- Creep (5)
- Aging (4)
- Fatigue (4)
- Additive Manufacturing (3)
- Cast iron (3)
- Residual stress (3)
- Stress relaxation (3)
- AGIL (2)
- AISI 316L (2)
- Additive manufacturing (2)
- Aluminum alloys (2)
- Cyclic softening (2)
- Elasticity (2)
- Electron microscopy (2)
- Fatigue damage (2)
- GMR (2)
- Metal magnetic memory (2)
- Number density (2)
- Ontologies (2)
- Ostwald ripening (2)
- P92 (2)
- Phase-field simulation (2)
- Plastic deformation (2)
- Precipitation (2)
- S-Phase (2)
- Tempered martensite-ferritic steel (2)
- Tensile strength (2)
- Thermo-mechanical fatigue (2)
- Thermomechanical fatigue (2)
- Ti-6Al-4V (2)
- Volume fraction (2)
- 316L (1)
- 9-12%Cr steel (1)
- Accessible (1)
- Acoustic emission (1)
- Advanced ceramic (1)
- Age hardening (1)
- Al-Cu alloy (1)
- Al-Cu-Li-alloy (1)
- Aluminum alloy (1)
- Al‐Cu‐Li‐alloy (1)
- Anisotropie (1)
- Automated image analysis (1)
- Axial-torsional Loading (1)
- Axial-torsional loading (1)
- Bitter technique (1)
- Brinell hardness (1)
- CKAN (1)
- Carbon capture and storage (CCS) (1)
- Casting skin (1)
- Ceramics (1)
- Characterisation (1)
- Chemo-mechanical coupling (1)
- Computed Tomography (1)
- Corrosion behaviour (1)
- Cracks (1)
- Creep behavior (1)
- Creep strength (1)
- Creep testing (1)
- Creep-fatigue (1)
- Creep-fatigue interaction (1)
- Crystal plasticity (1)
- Damage (1)
- Damage analysis (1)
- Data Interoperability (1)
- Data infrastructures (1)
- Data mapping (1)
- Deformation (1)
- Differential scanning calorimetry (DSC) (1)
- Digital image correlation (1)
- Digital representations (1)
- Digital workflows (1)
- Digitalizations (1)
- Domain Ontology Development (1)
- Dwell periods (1)
- Dwell times (1)
- EN AW-2618A (1)
- Elastic modulus (1)
- Elastische Energie (1)
- Emission coefficient (1)
- Environment (1)
- Expanding cavity model (1)
- FAIR (1)
- FAIR Data Management (1)
- FAIR principles (1)
- FAIR research data management (1)
- Fatigue assessment (1)
- Fatigue life time (1)
- Fatigue testing (1)
- Ferritic–martensitic steel (1)
- Fossil fuel power plants (1)
- Fracture (1)
- Fraktographie (1)
- Gamma titanium aluminide (1)
- Gamma-Titanium Aluminide (1)
- General Computer Science (1)
- General Engineering (1)
- General Materials Science (1)
- Growth kinetics (1)
- Hall-Petch relationship (1)
- Hardness (1)
- Heat resistant steels (1)
- Heat treatment (1)
- High Cycle Fatigue (HCF) (1)
- High efficiency power plants (1)
- Hocheffiziente Kraftwerke (1)
- IN 718 (1)
- In-situ Process Monitoring (1)
- Inconel 718 (1)
- Indentation (1)
- Industrial and Manufacturing Engineering (1)
- Interfacial anisotropy (1)
- Interoperable (1)
- Isothermal fatigue (1)
- Knowledge Representation (1)
- Knowledge graphs (1)
- Kohlendioxidabscheidung und -speicherung (CCS) (1)
- Korrosionsverhalten (1)
- Kriechen (1)
- Laser Powder Bed Fusion (1)
- Laser Powder Bed Fusion (LPBF) (1)
- Laser beam melting (LBM) (1)
- Laser irradiation (1)
- Laser powder bed fusion (1)
- Laser powder-based directed energy deposition (1)
- Laser-thermal shock (1)
- Life time prediction (1)
- Lifetime (1)
- Long-term aging (1)
- Low carbon steel (1)
- Low cycle fatigue (1)
- Low strain (1)
- Low-Cycle Fatigue (LCF) (1)
- Low-cycle fatigue (1)
- Magnetic domain distribution (1)
- Magnetic stray fields (1)
- Magneto-optical sensor (1)
- Magnetomechanical effect (1)
- Materials Testing (1)
- Materials informatics (1)
- Mechanical anisotropy (1)
- Mechanical properties (1)
- Mechanische Eigenschaften (1)
- Metal matrix composites (1)
- Microscopy (1)
- Microstructure evolution (1)
- Mikrostruktur (1)
- Miniature specimen (1)
- Misfitting precipitate (1)
- Molybdenum (1)
- Multiaxial deformation (1)
- Multi‐component diffusion (1)
- NDT (1)
- Neutron diffraction (1)
- Nickel-base alloy (1)
- Non-destructive Materials (1)
- Notch (1)
- Ontology (1)
- P91 (1)
- PBF-LB/M/316L (1)
- Parametric modeling (1)
- Phase‐field modeling (1)
- Precipitate shape (1)
- Precipitates (1)
- Process development (1)
- Quantitative Analyse (1)
- Radiation thermometry (1)
- Reference data (1)
- Reheating (1)
- Relaxation fatigue (1)
- Reproducibility (1)
- Reusable data (1)
- S-phase (1)
- SSiC (1)
- Safety (1)
- Selective laser melting (SLM) (1)
- Semantic Web Technologies (1)
- Shear modulus (1)
- Size effects (1)
- Solid solution softening (1)
- Solid solution strengthening (1)
- Standardisation (1)
- Strain difference (1)
- Stress distribution (1)
- Structural steel (1)
- Symmetric dwell periods (1)
- T1 precipitate (1)
- TIG weld (1)
- TMF (1)
- TNB-V5 (1)
- Temperature dependence (1)
- Temperature measurement (1)
- Tempered martensite ferritic steels (1)
- Tensile Test Ontology (1)
- Tensile properties (1)
- Tensile testing (1)
- Thermal barrier coating (TBC) (1)
- Thermal shock (1)
- Thermal shock stress (1)
- Thermo-mechanical Fatigue (1)
- Thermography (1)
- Thermomechanical Fatigue (TMF) (1)
- Thermomechanical Fatigue (TMF); High Cycle Fatigue (HCF); Cast iron; Fatigue assessment (1)
- Thermomechanical fatigue (TMF) (1)
- Thermoschock (1)
- Thickening (1)
- Titanaluminide (1)
- Titanium alloys (1)
- Topography (1)
- Transmission electron microscopy (1)
- Transmission electron microscopy (TEM) (1)
- Visual ontology development (1)
- Vocabulary providers (1)
- Warmfeste Stähle (1)
- Weibull statistics (1)
- Young's modulus (1)
- Yttria stabilized zirconia (1)
- microstructural changes (1)
- γ″ phase (1)
- θ′ phase (1)
- θ′-(Al2Cu) precipitate phase (1)
Organisationseinheit der BAM
- 5 Werkstofftechnik (27)
- 5.2 Metallische Hochtemperaturwerkstoffe (27)
- 8 Zerstörungsfreie Prüfung (9)
- 9 Komponentensicherheit (8)
- 5.1 Mikrostruktur Design und Degradation (7)
- 5.5 Materialmodellierung (6)
- 8.5 Röntgenbildgebung (6)
- 9.6 Additive Fertigung metallischer Komponenten (4)
- 9.3 Schweißtechnische Fertigungsverfahren (3)
- 9.4 Integrität von Schweißverbindungen (3)
MoSi alloys containing up to 1 wt.% Si were fabricated by powder-metallurgical processing and their lattice parameters, elastic constants, densities, grain sizes, strengths, ductilities, and fracture toughness values were measured. The yield strength was insensitive to the grain size, i.e., a HallPetch relationship was not observed. Generally, Si additions caused pronounced solid solution strengthening. However, for small Si concentrations (≤0.1 wt.%) solid solution softening was observed at room temperature and below. With increasing Si concentration, the room temperature ductility and fracture toughness dropped precipitously. This is attributed to the increase in strength and a transition from transgranular to intergranular fracture.
A miniature specimen geometry is presented that allows to extract small samples for tensile creep tests directly from critical components of steam generators in power plants like e.g. superheater tubes. In this way, material can be tested which has been subjected to the full processing chain of the component. The specimens then exhibit all microstructural modifications that are present in the component after the shaping process and heat treatment, and representative mechanical properties are determined. Similarly, specimens can be extracted from pre-corroded test pieces or used components after service to determine the impact of complex aging/loading/oxidation conditions during service on the mechanical properties of the material. The applicability of the miniature specimen test method is demonstrated in a comparative creep study involving standard and miniature specimens of P91 tempered martensite ferritic steel. Test results indicate satisfactory accuracy/repeatability of the method. Comparison with large scale specimen data reveals an influence of specimen size on the obtained creep behavior. These size effects need to be considered for a correct interpretation of results from miniature specimen creep tests.
The uniaxial, torsional and axial-torsional thermomechanical fatigue (TMF) behavior of the near-γ TiAl-alloy TNB-V5 was investigated. TMF tests were performed at 400-800 °C with mechanical strain amplitudes ranging from 0.15% to 0.7%. The tests were conducted thermomechanically in-phase (IP) and out-of-phase (OP).
For the same lifetimes, uniaxial IP tests required the highest strain amplitudes, while OP test conditions were most damaging and needed the lowest strain amplitudes. The Mises equivalent mechanical strain amplitudes of pure torsional tests were found in between uniaxial in-phase and out-of-phase tests for the same lifetimes. The non-proportional multiaxial out-of-phase test showed a lower lifetime at the same equivalent mechanical strain amplitude compared to the other types of tests.
The microstructure has been characterized applying electron microscopy and microstructural parameters such as fraction of twinned grains, grain size, lamellar distance and dislocation density have been quantified.
The fatigue behaviour of cast iron is usually investigated on machined specimens. Components of cast iron, however, have a casting skin; therefore the investigation of the influence of the casting skin on the lifetime is of interest. To study this influence isothermal fatigue tests were carried out on heat-resisting spheroidal graphite cast iron EN GJS SiMo 4.05 in 4–point-bending set-up at 400 °C. Specimens with and without casting skin were investigated comparatively. The number of cycles to failure was significantly lower for specimens with casting skin. Metallographic investigations underline the reduction of lifetime caused by casting skin.
A titanium (Ti-6242) matrix composite reinforced with continuous SiC fibers was studied. The mechanical behavior of the matrix and the composite was characterized by tensile, creep and isothermal fatigue tests at room temperature and up to 550°C. The thermo-mechanical fatigue behavior under in-phase and out-of-phase conditions was investigated for the composite between 100 and 550°C. Fracture surfaces were characterized by confocal light microscopy and by scanning electron microscopy to identify the damage mechanisms.
Der vorliegende Beitrag beschreibt typische Bruchmuster, die an SSiC Proben nach Thermoschockexperimenten beobachtet wurden und korreliert diese qualitativ mit der aufgebrachten Belastung. Der Thermoschock wird durch eine schnelle, in der Probenmitte beginnende spiralförmige Aufheizung dünner Scheiben mit Laserstrahlung realisiert. Durch diese Versuchsführung wandert ein zunehmender Temperaturgradient von der Mitte beginnend in radialer Richtung durch die Probe. Dieser Temperaturgradient ist für die Ausbildung von Druckspannungen im Probeninneren und Zugspannungen im kalten Randbereich der Probe verantwortlich. Beim Erreichen einer kritischen, versagensrelevanten Spannung tritt Probenbruch auf. Dabei wird die bis zu diesem Zeitpunkt in der Probe gespeicherte elastische Energie teilweise in die Schaffung von Rissoberflächen umgewandelt. Der Zusammenhang zwischen gespeicherter elastischer Energie und Bruchmuster wird dargestellt.
Thermal barrier coatings (TBCs) are used to increase the operating temperature of land-, sea-, or air-based turbines. As failure of the coating may result in serious damage of the turbine, reliable estimation of the lifetime is essential. Most experiments to assess the lifetime or to determine parameters for simulations of the behavior of TBCs are done by burner-rig-tests, where the operating conditions are simulated by cyclic heating of the surface and cooling of the backside of a coated sample.
In this work a possibility is presented to do comparable experiments by heating the surface with laser irradiation instead of a burner. For this purpose a Nd:YAG-laser with a maximum output power of 1?kW and a wavelength of 1064?nm is used. The laser spot can be moved by integrated optics across the sample surface to achieve homogeneous heating of the coating. Cooling of the backside is done by air. The temperature of the sample surface is determined by an infrared-camera which also enables the possibility to detect failures in the coating via thermography. Additionally, acoustic sensors attached to the sample holder are used to detect failures in the sample. The investigated ceramic material (yttria stabilized zirconia) has a very low absorption coefficient at the used laser wavelength. Therefore, a pre-treatment of the samples was needed to increase the absorption coefficient to be able to heat up the samples.
In this paper, the experimental setup and first experimental results are presented.
Thermal barrier coatings allow increasing the operating temperature and efficiency of land-, sea-, or air-based turbines. As failure of the coating may result in serious damage of the turbine, reliable estimation of its lifetime is essential. To assess the lifetime, cyclic tests are conceived to combine thermal loading by heating the surface of the coating with laser irradiation and nondestructive methods for damage determination. Using laser irradiation allows a high reproducibility of the thermal load. The temperature of the sample surface during thermal loading is determined by an infrared-camera which also enables the possibility to detect damage in the coating via thermography. Additionally, four acoustic sensors, attached to the experimental setup, are used to detect damage in the sample and determine the source of acoustic events. Results of acoustic emission correlate well with thermographic images that visualize the formation and evolution of damage through delaminations in the samples.
The continuing increase of steam parameters of fossil fuelled high efficiency power plants and new combustion concepts for the capture and storage of carbon dioxide lead to harsher service conditions for the components and structural materials of such facilities. The present work introduces a test concept that allows testing of candidate materials under simultaneous mechanical and corrosive loading. The material's reaction can be directly investigated under simulated temperature, load and corrosion conditions of modern installations. First results obtained for different heat resistant steels suggest a strong influence of the environmental medium on the fatigue and creep behaviour. Such findings complement the data that is available from the classical qualification process of the materials and may support the material selection for new power plant installations.