Study of Adhesive Wear Test on TiSi, AlTi, and WTi Coatings

Abstract

Coatings based on Ti, Si, W, and Al synthesized by different techniques have been investigated in order to better understand their properties; however, there are few results related to their wear behavior. In this paper, TiSi, AlTi, and WTi coatings were applied by means of a sputtering system on 316L stainless steel substrates in order to evaluate their behavior through a ball-on-disc wear test. Adhesive wear tests were carried out using the ball-on-disc technique, which allowed the coefficient of friction to be measured. The morphological characterization was based on an analysis of the SEM images and on the optical profilometry of the wear traces of the coatings, used to calculate the wear rate. An analysis of the wear products was carried out based on information provided by the SEM-EDS, Raman spectroscopy, and XPS techniques, which provided information about the tribo-chemical behavior of the coatings subjected to the ball-on-disc test. The morphological analysis showed that the TiSi and AlTi coatings exhibited premature failure, which was corroborated by means of the coefficient of friction curves. It was also observed that the WTi coating exhibited better behavior against the wear test, with a coefficient of friction lower than that of the stainless-steel substrate, without showing evidence of premature failure, which can be explained as a consequence of the tribo-chemical behavior of the WxOy produced in the coating.