Electroless deposition of SiC Nano Coating on Aluminium alloy and evaluation of wear resistance and electroless characteristics

Abstract

Electroless Nickel (ENi-P) and silicon carbide (SiC) is the major evolving surface coating technique employed in industries today. Many physical characteristics of EN coatings such as hardness, coating uniformity, wear resistance, and corrosion resistance makes this coating as a decision for many engineering applications. The major advantages of ENi-P coatings are uniform coating thickness, improved wear and hardness, ability to deposit on surface activated non-conductors etc. Typical anionic surfactant and various passive chemical additives and nano additives such as SiC were added to the EN bath. The coating was carried out on Aluminium alloy LM6. In this paper, Sodium Lauryl Sulphate (SLS) surfactants along with nano additives such as SiC were added to the EN bath. The effect of surfactant along with nano additives on surface properties such as wear properties, microhardness and microstructure of electroless nickel-phosphorus and silicon carbide coating was investigated. The microhardness was measured using Vickers hardness tester, the microstructure was examined by using Scanning Electron Microscope (SEM) and wear test was measured using Pin on disc machine. The result obtained from the above tests clearly indicates that the surfactant and passive additives improve the microhardness, microstructure and wear rate of ENi-P and SiC coatings significantly.