Effect of nitrogen pressure on structure and molten aluminum resistance of arc ion plated Cr-N coating on Ti-6Al-4V

Abstract

A series of Cr-N films were deposited on Ti-6Al-4V substrates by arc ion plating. At N2 pressures below 0.27Pa, the coatings contained 20-27at%N and consisted mainly of the Cr2N phase. Above this pressure, coatings contained more than 35at%N and mostly single-phase CrN. The dissolution rate of the Cr-N coating in molten aluminum was drastically decreased above an N content of about 35at%, which roughly corresponded to the transition point from Cr2N to CrN.