Properties of NiCrBSi coating, as sprayed and remelted by different technologies

The work is focused on the evaluation of mechanical properties of thermally sprayed NiCrBSi coatings, as-sprayed and further thermally post-treated by four different technologies (flame, furnace, electric resistance and high power laser remelting). The evaluation addresses specifically the coatings microstructure, hardness, modulus of elasticity, wear resistance and friction behavior. As a result of thermal post-treatment with all four used remelting technologies, the successful elimination of splat boundaries and decrease of coatings porosity were achieved. The difference between used remelting technologies was observed in the amount of dilution between coatings and substrate material, resulting in a decrease of measured Vickers microhardness and surface hardness and causing gradual changes of instrumented hardness and modulus of elasticity. The remelting enhanced the coating cohesion, which led to an increase of the abrasive wear resistance and corrosion resistance, but has low influence on the sliding wear behavior, irrespective of the used remelting technology.