Electrode erosion mechanism in the rod plasma injector type of generator as deduced from the structure of irradiated substrates

Titanium atoms were alloyed into a polycrystalline alindum substrate using various number of intense pulses consisting of plasma of the working gas and vapor and low energy ions of Ti erode from elecctrodes of the rod plasma injector type generator. Analyses of phase composition and of structural properties, as well as computer simulations of thermal evolution brought to the conclusion that increase of number of pulses leads to decrease of melting temperature of the top layer of the substrate. The erosion of the electrode material occurs during the last phase of the discharge via the vacuum arc mechanism.