Microstructural characterization of a Co-Cr-Mo laser clad applied on railway wheels

Artikel i vetenskaplig tidskrift, 2006

A Co–Cr–Mo laser clad applied on railway wheels is characterised by a combination of EBSD and EDX. A complete pass of the clad is investigated to achieve a better understanding of the microstructure evolution during laser cladding. A microstructure with columnar grains extending over the whole thickness of the clad is observed. The grains have a <001>-fibre texture with the fibre axis parallel to the normal of the substrate surface, and a substructure consisting of cells/dendrites. During the cladding process, two different kinds of precipitates form in the cell walls, which can be identified as M6C and a non-equilibrium phase. Furthermore, stacking faults are observed to occur in the clad grains and are discussed with respect to the laser cladding process.