Effect of current density on quality of electrodeposited Ni coatings by flexible friction

In order to improve the speed and quality of deposition, Ni coatings were prepared by a novel flexible medium friction assisted electrodeposition technology at different current densities. The microstructures and properties of the Ni electroplating were characterized by SEM, XRD, X-ray stress diffraction and micro hardness tester, respectively. The results show that the current density has important effect on the quality of electrodeposited Ni coatings by flexible medium friction. At the current density of 1-13 A/dm2, with increasing current density, the leveling power gradually becomes weaken by flexible medium friction, and the preferred orientation of Ni coatings transits from(111) crystal face to(200) crystal face. When the current density reaches 13 A/dm2, the electrodeposited Ni shows dual preferred orientation of(200) and(220) crystal face, but the degree is not too high. At the current density of 10 A/dm2, flexible medium friction assisted Ni electroplating has the lowest residual stress about 150 MPa, lowest surface roughness Ra of 0.48 μm, lowest porosity of 0.08 cm-2 and highest microhardness of 385 HV.