Steels and Alloys
Materials scientists try to develop alloys and steels that are lighter, stronger and more durable during their use. Therefore, the knowledge of the microstructural characteristics such as crystalline phases, presence of secondary phases and elemental distributions is mandatory for new products. Electron microscopy is the ideal method to analyse metals and similar materials in a multi-scale approach ranging from the micrometre to the atomic scale.
The ZFE’s long experience in metals characterisation allows fast and reliable solutions to improve product quality and efficiency:
- Evaluation of materials failures (fracture, corrosion)
- Microstructure characterisation in the scanning electron microscope (SEM)
- Precipitate and grain boundary analysis in the transmission electron microscope (TEM)
- Quality assurance of steels and alloy production
Materials produced in industry are all subject to fracture. Many of the failures are of special concern because of safety, environmental or legal considerations. Especially, the scanning electron microscope with X-ray spectrometry plays a central role in order to find the reason for failures. Additionally, we have established a fractography database which contains light microscopy, SEM, AFM, and TEM images in combination with mechanical data which helps us to identify materials failures fast and reliable.
Phase identification by elemental mapping
The detailed characterisation of bond failures by means of electron microscopy and x-ray spectrometry (SEM-EDX) helps to improve bondability and reliability of wire bonds in microelectronics.
Orientation analysis of crystal grains
Heat treatments leading to recrystallisation of steels and alloys are often used to tune the mechanical properties of these materials. Electron back scatter diffraction (EBSD) in the SEM allows the detailed investigation of the grain structure of superalloys, steels and light metals after homogenisation and hot forming. It also elucidates direct neighbourhood relationships between crystal grains.
Precipitate analysis in steels and alloys (1)
A very important problem in materials science is the visualisation of secondary phases embedded in a crystalline matrix e.g. precipitates and grain boundary phases in steels and alloys. The characterisation of their stereological parameters (size, distribution and volume fraction), chemistry and crystallography is best done in a TEM, which is additionally equipped with EDX- and EELS-spectrometers.
Precipitate analysis in steels and alloys (2)
Electron diffraction allows to study the crystal structure of secondary phases in materials. Compared to X-ray diffration, it has the advantage of high spacial resolution down to the nanometre regime.
Defect structures at atomic resolution
Aberration correction opened a new frontier in electron microscopy analysis providing atomic resolution imaging and analysis. We operate the unique ASTEM (FEI Titan 60-300 kV), which is equipped with a Cs-probe corrector (FEI-Titan 60-300). In combination with improved specimen preparation and advanced data analysis and simulation methods, we are able to study structural details in alloys like twins, grain boundaries, defects and interfaces.
Interested? Please do not hesitate to contact us:
Dr. Mihaela Albu | +43 (0) 316 873 8348
Dr. Stefan Mitsche | +43 (0) 316 873 8346
Want to know more?
Electronics and Semiconductor Devices
Paper and Fibres