Effect of bath temperature on nanocrystalline Ni-polytetrafluoroethylene composite coatings prepared by brush electroplating

Abstract

Brush electroplated Ni-polytetrafluoroethylene (PTFE) composite coatings with uniform distribution of PTFE particles in the nanocrystalline Ni matrix were prepared by changing the bath temperature. The effects of the bath temperature on the deposition, microstructure and tribological properties of the composite coatings were investigated. Experimental results show that the PTFE content in coatings, deposition rate and the tribological properties trend to increase with increasing bath temperature, and the composite coating prepared at the bath temperature of 40°C reaches a maximum in surface morphology. However, it is difficult to successfully prepare the composite coatings when the bath temperature is above 40°C owing to their poor adhesion to the substrate. Therefore, some measures should be taken when the composite coatings are prepared at the bath temperatures above 40°C.