Tarnish Resistance of Experimental Ti–Ag Alloys in 0.1% Na2S Solution

We developed experimental Ti–Ag alloys and characterized their ­properties. The mechanical properties and machinability of the Ti–Ag alloys were superior to those of pure titanium. The Ti–Ag alloy surfaces inhibited biofilm formation by Streptococcus mutans. The spontaneous formation of calcium phosphates on the Ti–Ag alloys upon immersion in simulated body fluid was confirmed. The corrosion resistance of the Ti–Ag alloys in a 0.9% NaCl solution and a 1% lactic acid solution was comparable to that of pure titanium. Further, we performed a tarnish resistance test, and found that the Ti–Ag alloys had excellent tarnish resistance in 0.1% Na2S solution, comparable or superior to that of pure titanium.