Contact Fatigue Properties of Nano-TiO₂/Ni Composite Coating Prepared by Electro-brush Plating

The nano-TiO2/Ni composite coating was prepared by electro-brush plating and its contact fatigue property was examined and the fracture morphology of nano-TiO2/Ni was analyzed by scanning electron microscope.The results show the surface topography of nano-TiO2/Ni is smooth and fine and large internal stress existe in the coating.Under a load of 60 N,contact fatigue life of nano-TiO2/Ni could reach to 1 400 000 cycles,obviously higher than that of the nickel coating.Under a load of 140 N,contact fatigue life of nano-TiO2/Ni is lower than that of the nickel coating.It is showed by failure analysis that under 60 N and 140 N plastic deformation and brittlement respectively are the main characteristics in the fracture morphology of nano-TiO2/Ni,and the fatigue cracks linearly propagated under the load of 140 N.