Surface Modification of 42CrMo Steel with TiB₂-Doped Ni60A Alloy Coatings

The surfaces of 42 CrMo steel, an automobile transmission-gear material, were modified with TiB₂-doped Ni60 A alloy coatings, deposited by high frequency induction cladding of the pre-covered layer of Ni60 A and TiB₂ powders.The influence of the TiB₂-content on the microstructures and tribological behavior of the coatings was investigated with X-ray diffraction scanning electron microscopy, energy dispersive spectroscopy and conventional mechanical probes.The results show that the TiB₂-doping had a major impact.For example, as the TiB₂-content increased, the thickness of the diffusion and cladded layers increased, the top-down decreasing hardness distribution curve shifted up, maximizing at 15%(wt),and the wear-rate and friction coefficient decreased.The adhesive and abrasive wears were found to account for the wear mechanisms.