Effect of heat treatment on friction and wear behavior of Ni-based thermal spray coating deposited on Z200C12 steel

The present work investigates Ni-based alloy coating deposited on Z200C12 steel using thermal spray technique. It focuses on the effect of annealing treatment at 500 & xfffd;C for different durations of 2 h, 4 h and 8 h on friction and wear behavior of the coatings. Phase composition, substrate/coating interface, elemental distribution and coating wear tracks morphologies were characterized using x-ray diffraction, scanning electron microscope, energy dispersive spectrometer and x-ray mapping techniques. Friction and wear resistance of the as-sprayed and annealed coatings were studied by determining the coefficients of friction and wear rates using an Al2O3 ball under a load of 6 N. The results showed that the heat-treated coating at 500 & xfffd;C for 2 h exhibited the highest wear resistance and a substantially lower friction coefficient as compared to all other coatings. The observed wear mechanisms mainly involved fragmentation of splats, brittle fracture, and abrasive wear.