Research Of Electroless Composite Plating Processing

Electroless Nickel Plating(ENP) have been widely applied in actual production with its advantages such as simple processing, low-cost, uniform thickeness and large-area plating. However, with the technological development and actual production's needs, it was gradually developed composite coatings with specific functions, Electroless Nickel Composite Plating(ENCP) could supplemented by the compound characteristics as maintaining nature of the original metal coating, attain strengthened and modified coatings; this makes the functions of composite coatings with considerable freedom.This paper discussed two different Electroless nickel composite platings : Ni-P-SiC composite platings and Ni-P-PTFE composite platings. SiC particles with high hardness are embodied in the Ni-P coatings by composite deposition. Hard particle dispersion strengthening greatly enhances the hardness and wear resistance of composite coatings. PTFE particles have good capability of self-lubricating and are dispersed in the nickel-phosphorus matix. When these compound coatings endure abrading, PTFE particles expand through its own layer rollout and form a lubricating layer on the surface of workpiece after abrading for a while.It helps reduce the friction coefficient and wear lost.It was studied the optimum conditions mainly by changing SiC(2-3μm) concentration and agitating methods, and optical microscopy, SEM, microhardness, Scratch friction and wear devices are used to characterize the composite coating microstructure and mechanical properties. Different...