Tribological Behavior of Ni-P Deposits on Dry Condition

The deposits of electroless Ni-P prepared by different process were studied by means of EPMA, XRD, microhardness tester, friction-wear instrument. The experimental results show that the microhardness of the deposits will change with different microstructures and heat treatment temperatures. The microhardness of as-plated deposit will increase upon increasing the content of the nanocrystalline phase in the matrix, which can be up to the microhardness of the Ni-P deposit heat treated at 400 °C for 1 h. The strengthening mechanism for Ni-P deposit is either solid solution strengthening or precipitation strengthening, which depends on the phosphorus content and the heat treatment temperature. The friction-wear results show that the Ni-P deposits consisting of more nanocrystalline phase exhibit better microhardness, lower friction coefficient before and after heat treatment at 400 °C, and good wear-resistant performances.