Abstract
Recently, non precious alloy is commonly used for dental treatment instead of precious alloy.But only a few studies were reported about its electrochemical behavior.The purpose of this study was the basic research for the study of application of electrolytic polishing and elctrolytic etching to Cr-Co-casting(Cr was contained 0〜50%)and Cr-Ni casting(Cr was contained 0〜20%).The relation between potential-current density curve(V-A urve)and potential sweep rate was observed, they were concerned each other, then reproducible and efficent potential sweep rate was considered 35mV/min.The ralation between V-A curve and electrolytic conditions(those were, the distance between electrodes, the area of positive electrode, concentration and temperature of phosphoric acid)and as cast or annealed metal.Findings were as follows 1.V-A curve was closely related to content of chromium.Less than 10% Cr, the value of electrolytic etching was higher, so this indicated in reference to corrosion resistance.2.Electrolytic coditions influenced V-A curves.a)Distance between electrodes(10〜40mm)had a little influence with V-A curve.b)According as area of positive electrode incresed, density of current became smaller, but potential of remarkable point did not change.c)Concentration and temperature of phosporic acid produced remarkably effect on V-A curve.3.Annealing(900℃ 1 hour)was considered no effect on electrolytic behavior.4.The value of decrease by electrolytic treatment under constant current density was in propotion to time of electrolytic treatment.
