| 摘要 |
PURPOSE:To improve the strength and corrosion resistance of the titled amalgam, by mixing an alloy powder of specific composition consisting of Ag, Sn and Cu as main components, and if necessary Zn and/or In with pure Ag powder in a specific amount. CONSTITUTION:An alloy powder having the composition of 45-65% Ag, 20-30% Sn, 10-25% Cu, 0-2% Zn and 0-3% InO is mixed with pure Ag powder such as an electrolytic Ag powder in an amount of 5-25% based on the alloy powder. A mercury amalgam obtained by adding several tens of % Hg to the mixed powder contains the gamma1 phase (Ag2Hg3) and little Cu6Sn5 phase and further an intermetallic compound of the beta1 phase (AgHg) in the reaction product, which remarkably improves the impact strength and corrosion resistance of the mercury amalgam. Therefore, the amalgam is ideal as a dental filling material, and the mixed metal powder has a very high industrial value. |
