Metallurgical characterisation

S&C components identified by anomalous readings will be extracted for extensive metallographic examinations, including electron microscopy, x-ray diffraction residual stress measurements and nano-hardness profiles. Special attention will be given to correlations between strain measurements and component condition. 3D X-ray tomography will be used for three-dimensional mapping of fatigue crack networks on rail surfaces and in bolts/screws. Laboratory investigation using controlled conditions to support the identification of failure mechanisms by establishing relations between cracks and microstructure. In-situ fatigue facilities for Scanning Electron Microscopy will be used to follow crack formation and propagation on a microscopic level. The following results are expected:

  • Damage assessment of components identified by anomalous readings, providing feedback to locate potentially damaged or worn out sections before failure takes place.
  • Identification of failure mechanisms in rails and bolts/screws using metallographic examinations of components from service condition and controlled laboratory tests.
  • Deliver recommendations for improvements in material choice and maintenance.