Friction coefficient and surface roughness of TiN‐coated HSS deposited using cathodic arc evaporation PVD technique

Abstract

Purpose

The purpose of this paper is to examine the effect of substrate temperature on friction coefficient and surface roughness of titanium nitride (TiN) coatings deposited on high‐speed steel (HSS) using commercially available cathodic arc evaporation physical vapour deposition system.

Design/methodology/approach

The goal of this work is to determine the usefulness of TiN coatings in order to improve the friction coefficient and surface roughness of HSS verses substrate temperature, as vastly used in cutting tool industry and many others. A Pin‐on‐Disc test was carried out to study the coefficient of friction verses sliding distance. Surface roughness of deposited coatings was studied via surface roughness tester and atomic force microscope (AFM).

Findings

Friction coefficient increased at higher temperature as compared to the coating deposited at lower substrate temperature. Surface roughness measured via both instruments showed similar trend in recorded data and, i.e. increased by increasing substrate temperature. AFM study showed that bearing ratio (per cent) decreased, whereas, fractal dimension increased with an increase in substrate temperature.

Research limitations/implications

It is implied that choosing a substrate temperature above 450°C in the existing coating system could damage some machine parts.

Practical implications

This scenario develops an approach to optimize the coating properties verses substrate temperature for specific application, such as cutting tools for automobiles and aircrafts.

Originality/value

The coating deposited at lower temperature showed better friction coefficient and surface roughness than the coating deposited at higher temperature and vice versa.

Citation

Ali, M., Hamzah, E. and Radzi Toff, M. (2008), "Friction coefficient and surface roughness of TiN‐coated HSS deposited using cathodic arc evaporation PVD technique", Industrial Lubrication and Tribology, Vol. 60 No. 3, pp. 121-130. https://doi.org/10.1108/00368790810871048