Wear and corrosion properties of (Ti 1– xCr x)N coatings produced by the ion-plating method

Abstract

(Ti 1– x Cr x )N coatings were deposited by an ion-plating technique in a reactor with two evaporation sources, Ti and Cr, which were evaporated by electron beam and resistance heating, respectively. The Ti and Cr concentrations in the coating were controlled by the Ti:Cr evaporation ratio. This study evaluated the wear and corrosion properties of the (Ti 1– x Cr x )N coatings. The wear properties were evaluated from the surface morphology, Cr content ( x) in the coatings and the effects of the wear debris as well as the transferred layer on the wear behavior were also examined. The wear resistance was found to increase when Cr was added to TiN. It was found from corrosion experiments that, at vs.·(SCE) <0.5 V, all samples showed an electrochemical behavior similar to that of the CrN coating, irrespective of the Cr content ( x) of the coatings. The coatings showed good passivity and the corrosion current was very small, regardless of the Cr content. Above 0.5 V, however, like the CrN coatings, the passivity disappeared and corrosion current increased abruptly.