Abstract
Surface modification was carried out on aluminum substrates using pulsed electrical discharges in an air or nitrogen atmosphere. With an aluminum electrode and alumina powder applied on the substrate, formation of aluminum-oxinitride occurs on the substrate surface. The synthesized aluminum-oxinitride is composed of aluminum supplied from the electrode and substrate, oxygen from the alumina powder and nitrogen from the atmosphere. The thickness of deposition layers increases as discharged current, pulsed width or duty factor which is the ratio of pulse width to a total pulse period increases. With an electrode of iron, titanium or nickel composite layers mainly consisting of aluminum-oxinitride and aluminide intermetallic compounds are formed. In addition to the above constituents, when the electrode is aluminum or titanium, the modified layers also contain each nitride.
