Effect of grain size on the tribological behavior of nanocrystalline nickel

Nanocrystalline nickel (8–28 nm) deposits were produced by direct and pulse current electrodeposition. The microhardness and microstrains in the deposits were estimated. Tribological testing indicated that the coefficient of friction (COF) for nanocrystalline nickel was almost half that of polycrystalline nickel. An important and interesting result is that extremely low COF of 0.16 can be obtained with nanocrystalline Ni coatings.