[Corrosion behavior of high copper amalgam (author's transl)].

In this paper, the experiments have been carried out to find the effects of additional copper and to find a correlation between the microstructure and the electrochemical behavior of dental amalgam. The corrosion behavior of high copper amalgam has been investigated by potentiostatic anodic polarization in 0.9% NaCl solution and compared with conventional dental amalgam. High copper amalgam become appreciably more noble (potential shift from -0.15 V to 0.5 approximately 0.8 V vs SCE). Such a behavior has been explained in terms of the solid state transformation which involves the elimination of the corrosion prone gamma 2 phase and the conversion of an electrochemically Cu6Sn5 intermetallic to a noble Cu3Sn.