Analysis of Novel Nano-composite Coating for Varied Combinations of YSZ1–x–y, TiNx, SiNy

Abstract

For over a decade, hard coatings have been providing wear resistance to cutting tools materials. The industrial prerequisites and advancements in hard coatings provide drastic improvements with respect to productivity and component lifetimes and hence reduce cost. However, selection of a desirable coating is often not straight forward, in view of the fact that the number of hard coating materials and their combinations are constantly increasing. The nano-composite coating materials are utilized, in order to have superior control over properties such as high chemical stability, wear resistance, and temperature of the coatings. This article discussed the development and application of an electrostatic spray coating process (ESC). This novel process exploits the creation of nano-composite coatings on cutting tool material, resulting in uniform thickness, high quality, and durability, with the intention to enhance the resistance to wear. The composition of ternary components in the deposited coating varies by weight percentage in five different compositions of YSZ1–x–y, TiNx, SiNy. Mechanical and tribological properties of nano-composite coatings are investigated. Scanning electron microscopy (SEM) was used to study the microstructure and wear morphology, in addition to energy-dispersive X-ray analysis (EDAX) and elemental mapping. With the aim to understand the interaction among wear behavior and coating properties, the mechanical tests including micro-hardness at ambient and elevated temperature were conducted. Scratch tests were performed to evaluate adhesive failure and critical load of coatings at room temperature. A tribometer was utilized to conduct dry sliding wear tests between a tungsten carbide pin coated with nano-composite and a Ti-6Al-4V disc. The ternary nanocomposite coating exhibited superior tribological properties compared to single and binary coatings. The composition that provides favorable results in relation to mechanical and tribological properties is preferred for coating the substrate to enhance the performance of the substrate in various industrial applications.