Surface chemistry of TiAlN and TiAlNO coatings deposited by means of high power pulsed magnetron sputtering

Abstract

It is shown that the investigated TiAlN and TiAlNO protective coatings show an enrichment of oxygen in the surface near region with concurrently higher oxidation states of titanium. We suggest that surface oxidation is caused by reaction with atmospheric oxygen at room temperature and/or with residual gas immediately after deposition during cooling in the chamber. As this coating system is used during cutting and forming operations, the here-established difference between the coatings composition and the composition of the surface near region of the coating is of great relevance for understanding the interactions thereof with the materials to be cut or formed.