牙用低贵金属合金机械性能的研究

Evaluation of mechanical properties of two low noble alloys

目的 :评价自行研制的两种低贵金属合金的机械性能。方法 :按照国家标准要求的规格用高频离心铸造机将两种低贵金属合金制成拉伸试棒 ,采用电子拉伸机测试 0 .2 %屈服强度、极限强度和延伸率及维氏硬度 ,并观察了不同热处理方式对合金材料力学性能的影响。结果 :两种合金均达到国家标准要求 ;合金的硬度较自然牙低 ;热处理方式对合金的力学性能影响显著 ,随着热处理温度的升高和处理时间的延长 ,合金的拉伸强度和硬度降低、延伸率增加。结论 :两种合金的机械性能可以满足临床修复体制作需要。

?Objective: To evaluate the mechanical properties of low noble alloy Au Pd and Ag Pd developed by Stomatological College,Fourth Millitaly Medical University and Xi'an University of Architecture & Techuology. Methods:The two low noble alloys were cast by means of a centrifugal induction furnace into the tensile bars whose dimensions accorded with the standards of China for Dental Casting Precious Metal Alloys. Tensile properties (δb)were determined by means of a conventional testing machine. The 0.2% offset yield strength(δ0.2), elongation(δ) and microhardness (HV)were determined in a conventional manner. All data were the average of four specimens of each alloy. Results:δb(MPa),δ0.2(MPa),δ(%) and HV of Au Pd were 485±12.9,365 ±14.8,7.8±1.1 and 220±14.3;those of Ag Pd 550±9.5,435±8.2,13.5±5.4 and 245±15.1,respectivey.Conclusion:The mechanical properties of the two low noble alloys meet the demands of standards and have lower microhardness than natural tooth enamel.