Fraunhofer Institute for Mechanics of Materials IWMThe microstructure determines the properties of materials — and thus also the properties of the components manufactured from them — and is set by a defined sequence of manufacturing steps. It can also change, either positively or negatively, during operation. We uncover the relationships between the microstructure and the material’s properties and use this information to develop optimized materials properties and ensure safe use of materials. These developments can, for example, concern mechanical properties, long-term behavior, service life, abrasive properties, or corrosion properties. Through simulations using various software solutions, we can predict microstructures and evaluate them in terms of the reliability, safety, and service life of components. Building on this, we develop concepts for component design and manufacturing optimization.
Analysis and Simulation of Microstructure Formation
We investigate the relationships between a material’s microstructure and its functionality, properties, and potential degradation and damage
- Corrosion damage, stress corrosion cracking
- Fatigue, embrittlement, and hydrogen diffusion
- Strength and formability
- Work-hardening
- Function of wear- and corrosion-resistant coatings
- Heat treatment
- Crack propagation, failure risks, and safety
We quantitatively determine microstructural properties using a variety of methods
- Microscopy (optical, scanning electron microscopy - SEM)
- Particle and pore analyses (volume fraction, size distributions, shape factors)
- Hardness measurement (core hardness, hardness profiles, hardness mapping)
- Hardness testing methods according to Vickers, Brinell, Knoop, Rockwell, Shore A
- Manual and automatic (for hardness mapping or hardness profiles)
- All standard load ranges, including those per DIN 6507, 4545, 6506, or ASTM E384, E92, E384, E10
- Nanohardness measurement with nanoindenter:
- Hardness measurement according to DIN EN ISO 14577
- Creep loads adjustable up to 60 s
- Force range 0.4–1000 mN
- Measurable hardness range 0.001–120,000 N/mm²
- Vickers and ball indentation
- Automatically movable measuring stage for hardness mapping
- Quantitative microstructure analysis (optical, EBSD, XRD)
- Determination of crystal and grain orientation, texture, grain deformation, and generation of orientation maps
- Coupling with EDX possible
- Angular accuracy approx. 1°
- Method for determining the chemical composition of materials (GDOES)
- Chemical composition of metals
- Depth profiles possible up to approx. 100 µm
- Calibrated for Fe- and Ni-based materials
- Analysis of local chemical composition with EDX, EDAX:
- Measurement of local chemical composition
- Elements with atomic number 6 or higher (carbon) can be measured
- Carbon cannot be quantified
- Lateral resolution depends on sample material (approx. 1 µm)
- Measurement of chemical composition at defined points, along lines, or via element mapping
- X-ray diffraction and semi-destructive residual stress and phase analyses
We model material behavior and make predictions regarding material microstructure. To do this, we calculate microstructural changes during manufacturing processes and in service using software such as Thermocalc, Dictra, Matcalc, Sysweld, and our own codes.