Structure and Phase Composition of a Ti Film–Al Substrate System Irradiated with an Intense Pulsed Electron Beam

Abstract

Commercially pure A7 aluminum was exposed to surface modification in a single vacuum cycle which included vacuum arc evaporation and deposition of commercially pure titanium and intense electron beam irradiation and melting of the film–substrate system using a plasma-cathode pulsed electron source. The deposited Ti film thickness was 0.5 and 1 μm. The irradiated Ti–Al system revealed a multilayer multiphase structure consisting of submicro-and nanosized elements with intermetallic inclusions Al3Ti, Al2Ti, and TiAl3. The Ti film during irradiation broke up into fragments with their immersion in the molten Al surface layer to a depth of 20 μm. The modified material surpassed the initial aluminum in wear resistance by a factor of 2.4 and in microhardness by a factor larger than 4. The main cause for the high surface hardness and high wear resistance of the modified aluminum was likely the formation of both the intermetallic particles and the Ti-hardened transition layer.