Characteristics of alumina coating on SAE 52100 bearing steel with Ni-Cr bond coat

Abstract

The characteristics of alumina coating deposited on SAE 52100 bearing steel substrate with and without Ni-Cr bond coat were compared in this research work. The bond coat refers the deposition of Ni-Cr elements on the bearing steel substrate for 50 microns coating thickness and top of it alumina was deposited for a coating thickness of 150 micron. Plasma spray process is used for depositing Al2O3 particles on SAE 52100 steel substrate. The microstructure and phase details were analysed by the SEM and XRD techniques. An effect of bond coat on insulation resistance, bond strength, scratch resistance, thermal stability, drop test for electrical resistance and corrosion resistance properties were analysed. The significance of Ni-Cr bond coat is observed in thermal stability, corrosion resistance and bond strength.