[Corrosion of dental titanium alloys binary system of Ti-Al, Ti-Cu, Ti-Ni].

Anodic polarization, natural electrode potential, polarization resistance, tarnish, weight change and metal component dissolution in artificial saliva, of Ti-Al, Ti-Cu and Ti-Ni binary alloys were investigated to determine the effects of the added elements on the corrosion characteristics. In the case of Ti-5 at % Al to Ti-50 at % Al system alloys, increase in the aluminum content of the alloys raised the corrosion resistance. However pitting corrosion presumed at an aluminum content of more than 10 at %. In the case of the Ti-5 at % Cu to Ti-70 at % Cu system alloys, increase in the copper content of the alloys decreased the corrosion resistance and the decrease was marked at a copper content of more than 50 at %. In the case of Ti-5 at % Ni to Ti-70 at % Ni system alloys, 50 at % Ni was estimated to be the maximum content to keep corrosion resistance of the titanium alloys.