Study on wear, corrosion and fatigue properties of dual metallic bearings coated with nickel and aluminum particles

Abstract

One of the solutions for improving the mechanical properties is coating them with particles, which is carried out by various methods. In this study, dual metallic copper/steel bearings were investigated so that, one of them was an uncoated (S0) and three coated samples, nickel micro-particles (S1), nickel/aluminum micro-particles (S2), and nickel/aluminum nano-particles (S3) were produced. The samples were subjected to mechanical tests including micro hardness, wear, and scratch, and then their corrosion rate and fatigue life were evaluated. The results showed that creating a nano-sized coating on the sample improved their properties compared to the micro-sized and uncoated samples. The highest micro hardness was obtained for sample S3, which was equal to 103.6 HV, 18% higher than sample S0. The lowest wear and corrosion rates were also obtained for sample S3, which were equal to 0.38 mg m−1 and 3.14 mm year−1, respectively. Also, sample S3 had lowest delamination amount in the scratch test equal to 0.17 mm and most number of cycles until failure, 242 thousand cycles, in the fatigue test which was 76% more than the number of cycles spent on sample S0. Additionally, the microstructure of the corroded and worn surfaces of samples were examined by SEM imaging.