Cracking resistance of Cr3C2-NiCr and WC-Cr3C2-Ni thermally sprayed coatings under tensile bending stress

The cracking behaviour of Cr3C2-25(Ni20Cr) and WC-20Cr3C2-7Ni thermally sprayed coatings during tensile load in 3-point bending tests was studied by Acoustic Emission (AE) monitoring and microstructure post-analysis. The AE monitoring reveals a superior resistance against cracking in the WC-Cr3C2-Ni coatings compared to Cr3C2-NiCr. The incorporation of tungsten carbides beneficially affects the residual stress state of the coatings and has an impact on the detailed fracture mode. The results hold for both as-sprayed as well as ground and polished coatings.