LAUSR

Abstract The influence of the processes of dissolution/precipitation of strengthening phases during high-temperature treatment of NiCrBSi laser clad coating on the microhardness and tribological characteristics during sliding over the fixed abrasive is considered. Rapid melt solidification during laser cladding contributes to the development of thermally activated phase transformations. Heating to 1000 °C causes the Ni3B dissolution a decrease in microhardness and resistance to abrasive wear of the coating. With a gradual decrease in the cooling rate from 1000 °C (cooling of the samples in air, in a muffle and in a vacuum furnace), nickel borides and silicides are precipitated and the hardest strengthening CrB and Cr7C3 phases are coarsened. This leads to an increase in hardness and wear resistance of the coating.