Surface modification of the Al0.1CoCrFeNi high-entropy alloy by solid carburization via isochronal spark plasma sintering

Carburization by spark plasma sintering process is successfully employed in surface modification of Al0.1CoCrFeNi high entropy alloy. The carburized coating has a double-layer structure and contains two types of carbide precipitates (M7C3 and M23C6). The surface Vickers hardness shows a gradient decreasing trend, and the highest hardness is about three times that of the matrix. Nanoindentation tests are performed to investigate the nanoscale mechanical properties of different phases at different distances from the coating surface. The wear resistance of carburized coating is also assessed based on the nanoindentation results. This research results indicate that the hardness and wear resistance of the carburized coating have been greatly improved.