Materials technology

Studies are focused on the fatigue behavior in service but includes also the deformation behaviour of metals in manufacturing processes like heat treatment, forming and welding. Experiments are conducted in fatigue test rigs with thermomechanical (TMF) and Axial-Torsion capabilities, complemented with microscopy, image analysis, X-ray diffraction and tomography. The mechanical properties are often implemented into material models used for computation.

Examples of current research projects

• Prediction of thermomechanical fatigue (TMF) in engine cylinder heads allowing optimization of hybrid engine operation leading to decreased fuel consumption. Industrial partner: Volvo Cars.
  
  
• Rolling contact fatigue (RCF) cracking in the anisotropic surface layer of railway wheels and rails. Understanding of crack formation and prediction of the severity of cracks formed is needed for safe operation and decreased maintenance costs. Advanced microstructure characterization is done in cooperation with Denmark Technical University.
  
  
• Higher strengths steels in rails often lead to larger sensitivity for thermal damage in operation and on maintenance. To model this, advanced characterization of the thermomechanical behavior including constitutive relations, phase transformations and dilatation is needed. The project is done in close collaboration with IMS – Material and computational mechanics.

 
Both railway projects are supported by several industrial partners within CHARMEC and the EU-project SHIFT2RAIL.

All research helps improving the competitiveness of more sustainable solutions, with decreasing consumption of fossil fuels.