Microstructure, mechanical properties and tribological behaviors of gold coating determined by surface quality

Abstract

Gold-plated electrical contacts have been widely applied in engineering due to their excellent features and the ever-growing interest in microelectronic products. However, gold coatings have extremely low hardness and load-bearing capacity, limiting their reliability, wear resistance and lifespan. This study deposited gold coatings on the surface of electrical contacts by employing magnetron sputtering at varying powers. The effects of sputtering power on the microstructure, mechanical properties and wear resistance of coatings were elaborated using the growth mode and wear theory. The results show that increasing the sputtering power from 100 to 500 W enhances the densification, crystallinity, and (111) preferred orientation of the gold coating, resulting in improved adhesion strength, mechanical properties, and tribological behaviors. This study proposed the reasons for the outstanding properties of the coatings, along with theoretical analysis and experimental results.