Structure and mechanical properties of pure titanium film deposited onto TiNi shape memory alloy substrate by magnetron DC sputtering

In order to improve the biocompatibility of TiNi shape memory alloy, coating of the alloy substrates with pure titanium films by magnetron DC sputtering in Ar gas was examined and the effects of the substrate temperature (ranging from 20 to approx. 400 degreesC) on the formation of the titanium film were investigated. The titanium films deposited under various substrate temperatures appeared to be uniform and adhesive. Under SEM, the surface morphology of the obtained titanium films gradually changed from the structure consisting of fine particles to that of fine fibers with increase in substrate temperature. Based on XRD, it was concluded that each of the films consisted of alpha-titanium phase. (C) 2004 Elsevier B.V. All rights reserved.