5 Werkstofftechnik
Filtern
Erscheinungsjahr
- 2019 (108) (entfernen)
Dokumenttyp
- Vortrag (57)
- Posterpräsentation (29)
- Beitrag zu einem Tagungsband (14)
- Zeitschriftenartikel (7)
- Forschungsdatensatz (1)
Sprache
- Englisch (108) (entfernen)
Referierte Publikation
- nein (108) (entfernen)
Schlagworte
- Corrosion (13)
- Additive Manufacturing (12)
- Glass (11)
- Microstructure (7)
- CO2 (5)
- Carbon steel (5)
- Crack growth (5)
- Water content (5)
- Additive manufacturing (4)
- CCS (4)
- Ceramic (4)
- EBSD (4)
- Fatigue (4)
- Low Cycle Fatigue (4)
- Transmission electron microscopy (4)
- 316L (3)
- Alloy 2618A (3)
- Anisotropy (3)
- Ceramic spring (3)
- DCB (3)
- Degradation (3)
- Diffraction (3)
- Diopside (3)
- Modeling (3)
- Orientation (3)
- Oxidation (3)
- P92 (3)
- Pitting (3)
- Slurry (3)
- Tempered Martensite Ferritic Steels (3)
- Thermo-Mechanical Fatigue (3)
- Utilization (3)
- 3D printing (2)
- Aluminium (2)
- CCU (2)
- Capture (2)
- Carbon (2)
- Carbon capture (2)
- Ceramics (2)
- Coarsening (2)
- Computed Tomography (2)
- Condensation (2)
- Corrosion Fatigue (2)
- Crack Propagation (2)
- Creep-Fatigue (2)
- Crevice corrosion (2)
- Crystal plasticity (2)
- Crystallization (2)
- Digital material representation (2)
- Distribution function (2)
- FeCr- alloys (2)
- Fiber reinforced polymer (2)
- Fracture surface analysis (2)
- Full-Notch Creep Test (FNCT) (2)
- Glas (2)
- Glass fiber reinforced polymers (2)
- High Alloyed Steel (2)
- High Temperature Testing (2)
- High temperature (2)
- High temperature corrosion (2)
- IR (2)
- In situ (2)
- Internal friction (2)
- Laminography (2)
- Layerwise (2)
- Lightweight materials (2)
- Monte-Carlo Simulation (2)
- Non-destructive testing (2)
- Photon counting detector (2)
- Polyethylene, PE-HD (2)
- Polymer (2)
- Polymer matrix composites (2)
- Powder (2)
- Roughness (2)
- Sandwich (2)
- Scale-bridging (2)
- Selective laser melting (2)
- Simulation (2)
- Sintering (2)
- Soda-lime silicate glass (2)
- Steel (2)
- Storage (2)
- Sulfidation (2)
- Surface (2)
- Surface crystallization (2)
- Synthetic air (2)
- Tensile Properties (2)
- Ti-6Al-4V (2)
- Titanium (2)
- VSSA (2)
- Virtual experiments (2)
- Water speciation (2)
- Weibull Distribution (2)
- Wind energy (2)
- Wind turbine blades (2)
- Zero-g (2)
- µ-gravity (2)
- 3D imaging (1)
- 5G (1)
- AM (1)
- Aggressive environment (1)
- Al-Cu-Li alloys (1)
- Alkali-activated materials (1)
- Aquifer (1)
- Atomization (1)
- BTS (1)
- Bioceramics (1)
- Blähen (1)
- Breakdown strength (1)
- Brittle fracture (1)
- CALPHAD (1)
- CALPHAD databases analysis (1)
- CCUS (1)
- CO2 Corrosion (1)
- CO2-storage (1)
- Calibration (1)
- Carbidic austempered ductile iron (1)
- Carbon Capture, Utilization and Storage (CCUS) (1)
- Carbon storage (1)
- Cement (1)
- Certification Standard 22 (1)
- Chemically Complex Alloy (1)
- Chemo-mechanical coupling (1)
- Co-axial monitoring (1)
- Complex concentrated alloy (CCA) (1)
- Composite (1)
- Corrosion and storage (CCUS) technology (1)
- Corrosion resistance (1)
- Crack healing (1)
- Crack propagation (1)
- Creep (1)
- Crystal Plasticity Modelling (1)
- Crystal orientation (1)
- DED-L (1)
- Dark-field transmission electron microscopy (DFTEM) (1)
- Data storage (1)
- Deformation behavior (1)
- Dense phase (1)
- Destabilization (1)
- Dielectric strength (1)
- Dislocation (1)
- Dislocations (1)
- Distributed fiber optic sensors (1)
- Droplet (1)
- Droplet corrosion (1)
- Dual-energy (1)
- Ductile iron (1)
- Dynamic mechanical analysis (1)
- Dynamisch Mechanische Analyse (1)
- EASA (1)
- EIS (1)
- Early oxidation (1)
- Elastic constants (1)
- Electrochemical deposition (1)
- Electrochemical dressing (1)
- Electromicroscopy (1)
- Electron backscattered diffraction (EBSD) (1)
- Electron energy (1)
- Electropolishing (1)
- Endurance Limit (1)
- Energy distribution (1)
- Environmental stress cracking (1)
- Environmental stress cracking (ESC) (1)
- Failure test (1)
- Fatigue Life Evaluation (1)
- Fiber reinforced polymers (1)
- Fine Powder (1)
- Flowability (1)
- Foaming (1)
- Force-distance diagram (1)
- Freeze Drying (1)
- Fresnoit (1)
- Geothermal (1)
- Glass ceramic (1)
- Glass matrix composite (1)
- Glass powder (1)
- Glass screening device (1)
- Glass-ceramic (1)
- Hard machining (1)
- Hardness (1)
- Heat treatment (1)
- Heißgasextraktion (1)
- High alloyed steel (1)
- High entropy alloys (1)
- High-entropy alloys (1)
- High-temperature corrosion (1)
- Honing (1)
- Honing Stone (1)
- Inconel 686 (1)
- Irregular topography (1)
- Kikuchi pattern (1)
- Kristallisation (1)
- LMD (1)
- LTCC multilayer (1)
- Laser Beam Melting (1)
- Laser Scanning Microscopy (1)
- Laser Scanning Microscopy (LSM) (1)
- Laser cladding (1)
- Laser-induced slip casting (1)
- Layerwise Slurry Deposition (1)
- Layerwise slurry deposition (1)
- Machine Learning (1)
- Material degradation (1)
- Materials science (1)
- Mechanical behavior (1)
- Mechanical properties (1)
- Metal powder characterization (1)
- Metrology (1)
- Microhardness (1)
- Micromechanical model (1)
- Microstructure analysis (1)
- Microstructure characterisation (1)
- Microstructure evolution (1)
- Microstructure modification (1)
- Mixed Ca-K-Na phosphates (1)
- Mortel (1)
- NDT (1)
- NMR (1)
- Na and K rhenanites (1)
- Nano particle (1)
- Nano screening (1)
- Nanoparticles (1)
- New standards (1)
- Niobium alloying (1)
- Nondestructive testing (1)
- Ooxidation (1)
- Optical criterion (1)
- Particle size (1)
- Phase diagram (1)
- Phase transformation (1)
- Phase transformations (1)
- Phase-field simulation (1)
- Physically based material model (1)
- Pipeline (1)
- Pipelines (1)
- Polyaniline (1)
- Pores (1)
- Power plant (1)
- Process Monitoring (1)
- Process monitoring (1)
- Repair patch (1)
- Residual stress (1)
- Sailplane Development Panel (1)
- Salt melt (1)
- Sandwich structures (1)
- Scanning Electron Microscopy (SEM) (1)
- Scanning electron microscopy (1)
- Sensor (1)
- Silicon Carbide (1)
- Silver glass paste (1)
- Sintern (1)
- Slip-rolling (1)
- Slow crack growth (1)
- Soda-lime-silica glass (1)
- Spectroscopy (1)
- Spring constant (1)
- Spring constant (1)
- Superalloy (1)
- Supercritical CO2 (1)
- Supercritical/dense phase CO2 (1)
- TEM (1)
- Tempered martensite ferritic steel (1)
- Tempered martensite ferritic steels (1)
- Tensile testing (1)
- Thermodynamic analysis (1)
- Thermomechanics (1)
- Transmission electron microscopy (TEM) (1)
- Ultrasound (1)
- Utilization, and storage (CCUS) technology (1)
- VM12 SHC (1)
- Vacuum hot extraction (1)
- Vickers (1)
- Vickers indentation (1)
- Wind turbine blade shells (1)
- alumina (1)
- arbon capture (1)
- bioactive (1)
- biomaterials (1)
- bone (1)
- carbon steel (1)
- ceramics (1)
- condensate (1)
- corrosion (1)
- electrochemical characterization (1)
- impurities (1)
- microstructure analysis (1)
- pitting corrosion (1)
- selective laser melting (1)
- utilization, and storage (CCUS) technology (1)
- volume resistivity (1)
Organisationseinheit der BAM
- 5 Werkstofftechnik (108) (entfernen)
Eingeladener Vortrag
- nein (57)
Additive manufacturing of alkali-activated materials currently attracts a lot of attention, because of the possibility to produce customized high-performance elements for a range of applications, potentially being more resource-efficient than conventionally produced parts. Here, we describe a new additive manufacturing process for alkali-activated materials that is based on selective laser-heating of lithium aluminate/microsilica slurries. The new process-material combination allows to manufacture elements with complex geometries at high building rates and high accuracy. The process is versatile and transferrable to structures of sizes differing by orders of magnitude. The mechanical strength of the obtained materials was in the range of values reported for conventional metakaolin-based geopolymers, and superior to what has been hitherto reported for alkali-activated materials produced by additive manufacturing. This mechanical performance was obtained despite the fact that the degree of reaction of the lithium aluminate and the microsilica was low, suggesting that significant reactions took place only at the surface of the microsilica particles.
Powder bed -based technologies are amongst the most successful Additive Manufacturing (AM) techniques. "Selective laser sintering/melting" (SLS/SLM) and "binder jetting 3D printing" (3DP) especially are leading AM technologies for metals and polymers, thanks to their high productivity and scalability. In this context, the "layerwise slurry deposition" (LSD) has been developed as a layer deposition method which enables the use of SLS/SLM and 3DP technologies for advanced ceramic materials. LSD consists in the layer-by-layer deposition of a ceramic slurry by means of a doctor blade. Each layer is deposited and dried to achieve a highly packed powder layer, which can be used for SLM or for 3DP. This technique offers high flexibility in the ceramic feedstock used, especially concerning material and particle size, and is capable of producing parts with physical and mechanical properties comparable to traditionally shaped parts. In this presentation, the LSD technique will be introduced and several examples of application to porcelain, SiC and alumina products will be reported.
The layerwise slurry deposition (LSD) has been established in the recent years as a method for the deposition of ceramic powder layers. The LSD consists in the layer-by-layer deposition of a ceramic slurry by means of a doctor blade; each layer is sequentially deposited and dried to achieve a highly packed powder layer.
The combination of binder jetting and LSD was introduced as a novel technology named LSD-print. The LSD-print takes advantage of the speed of binder jetting to print large areas, parallel to the flexibility of the LSD, which allows the deposition of highly packed powder layers with a variety of ceramic materials.
The working principle and history of the LSD technology will be shortly discussed. A theoretical background will be also discussed, highlighting advantages and drawbacks of the LSD compared to the deposition of a dry powder.
The last part of the talk will be dedicated to highlight recent results on the LSD-print of SiSiC of geometrically complex components, in collaboration between BAM and HC Starck Ceramics GmbH. Density, microstructure and mechanical properties of LSD-printed and isostatic pressed samples will be discussed and compared.
During their lifetime, polymer components subjected to mechanical loads and environmental influences show a loss of their mechanical properties required for their specific applications. In this respect, the craze-crack damage mechanism slow crack growth (SCG) is relevant for PE-HD components used in high-performance applications such as pipes and containers for the storage and transport of dangerous goods. SCG is considered to be the major failure mechanism in polyolefins and it typically occurs suddenly and unexpectedly. Due to the fields of application, SCG is a safety relevant issue. To test for the resistance of PE-HD pipe and container materials against SCG, the full-notch creep test (FNCT) is widely applied in Europe. In this study, SCG phenomena in PE-HD are investigated in detail based on an improved FNCT, especially including the consideration of the influence of environmental liquids effecting the damage mechanism. Using an enhanced fracture surface and a crack propagation analysis with imaging techniques such as light microscopy (LM), laser scanning microscopy (LSM), X-ray computed tomography (CT-scan) and scanning electron microscopy (SEM), detailed data concerning SCG are obtained.
The combined application of FNCT and such imaging techniques is explicitly advantageous and recommended to gain important information on damage occurring to PE-HD induced by mechanical stress and the influence of environmental liquids, which is essential within the Fourth Industry Revolution.
Powder bed -based technologies are amongst the most successful Additive Manufacturing (AM) techniques. "Selective laser sintering/melting" (SLS/SLM) and "binder jetting 3D printing" (3DP) especially are leading AM technologies for metals and polymers, thanks to their high productivity and scalability.
However, the flowability of the powder used in these processes is essential to achieve defect-free and densely packed powder layers. For standard powder bed AM technologies, this limits the use of many raw materials which are too fine or too cohesive.
This presentation will discuss the possibilities to either optimize the powder raw material to adapt it to the specific AM process, or to develop novel AM technologies which are able to process powders in a wider range of conditions.
In this context, the "layerwise slurry deposition" (LSD) has been developed as a layer deposition method which enables the use of very fine ceramic particles.
Powder bed -based technologies are amongst the most successful Additive Manufacturing (AM) techniques. "Selective laser sintering/melting" (SLS/SLM) and "binder jetting 3D printing" (3DP) especially are leading AM technologies for metals and polymers, thanks to their high productivity and scalability.
However, the flowability of the powder used in these processes is essential to achieve defect-free and densely packed powder layers. For standard powder bed AM technologies, this limits the use of many raw materials which are too fine or too cohesive.
This presentation will discuss the possibilities to either optimize the powder raw material to adapt it to the specific AM process, or to develop novel AM technologies which are able to process powders in a wider range of conditions.
In this context, the "layerwise slurry deposition" (LSD) has been developed as a layer deposition method which enables the use of very fine ceramic particles. Another technology, the Gas Flow Assisted Powder Deposition, can increase the stability of the powder bed and the packing density, even in extreme conditions such as in absence of gravitational forces.
An overview of the BAM funed Focus Area Materials Project "AGIL" will be presented. AGIL focussed on the stdiy of the ageing characteristics of additively manufactured austenitic stainless steel with a "powder to mechanical failure" Approach. Recent Highlights are presented and a perspective for future studies.
The full-notch creep test (FNCT) is a common method to evaluate the environmental stress cracking (ESC) behavior of high-density polyethylene (PE-HD) container materials . The test procedure as specified in ISO 16770 provides a comparative measure of the resistance against ESC using the time to failure of specimens mechanically loaded in a well-defined liquid environment. Since the craze-crack damage mechanism underlying the ESC process is associated with brittle failure, the occurrence of globally brittle fracture surfaces is a prerequisite to consider an FNCT measurement as representative for ESC . Therefore, an optical evaluation of FNCT fracture surfaces concerning their brittleness is essential. Due to the experimental setup, an inevitable increase of the true mechanical stress and the associated appearance of small ductile parts on fracture surfaces is induced in any case. Hence, an FNCT experiment is considered as 'valid', if the corresponding fracture surface is predominantly brittle . Based on laser scanning microscopy (LSM) height data of FNCT fracture surfaces , a universal and easy-to-use phenomenological criterion was developed to assess the validity of distinct FNCT experiments. This criterion is supposed to facilitate a quick evaluation of FNCT results in practical routine testing.
Characterization of early crystallization stages in surface-crystallized diopside glass-ceramics
(2019)
Structure formation in glass-ceramics by means of surface crystallization is a challenging open question and remains elusive to definite answers. In several glass-ceramic systems, oriented crystal layers have been observed at the immediate surface, including diopside and some fresnoite systems. However, it is still open to debate, whether oriented surface crystallization is the result of oriented nucleation or growth selection effects. In the same vein, there is still discussion whether surface nucleation is governed by surface chemistry effects or by defects serving as active nucleation sites.
In order to help answer these questions, annealing experiments at 850°C have been performed on a MgO·CaO·2SiO2 glass, leading to the crystallization of diopside at the surface. Different annealing durations and surface treatment protocols (i.a. lapping with diamond slurries between 16 µm and 1 µm grain size) have been applied. Particular focus has been put on earliest crystallization stages, with crystal sizes down to about 200 nm. The resultant microstructure has been analyzed by electron backscatter diffraction (EBSD) and two different kinds of textures have been observed, with the a- or b-axis being perpendicular to the sample surface and the c-axis lying in the sample plane. Even at shortest annealing durations, a clear texture was present in the samples. Additionally, selected samples have been investigated with energy-dispersive x-ray spectroscopy in the scanning transmission electron microscope (STEM-EDX). The diopside crystals have been found to exhibit distinguished submicron structure variations and the glass around the crystals was shown to be depleted of Mg.