Effect of TiB₂ Additives on Wear Behavior of NiCrBSi-Based Plasma-Sprayed Coatings

The influence of titanium diboride additives on microstructure and wear resistance of NiCrBSi thermally sprayed coatings deposited on a steel substrate has been studied. NiCrBSi-based composite powders with 10, 20, 40 wt.% TiB2 particles content were produced. The structure of NiCrSiB-TiB2 coatings consists of TiB2 and CrB grains distributed in Ni-based matrix. The wear resistance of NiCrSiB-TiB2 plasma sprayed coatings in dry sliding conditions against the same coating using pin-on-disk tester. It was determined that the amount of titanium diboride particles in NiCrBSi-based coatings influences essentially on the wear resistance and wear mechanism. The NiCrBSi-based plasma sprayed coatings containing 20 wt.% of TiB2 possess the high wear resistance due to the realization of mechanical-oxidation wear mechanism