稀土银铜合金的高温氧化

HIGH-TEMPERATURE OXIDATION OF RARE-EARTH ELEMENTS-SILVER-COPPER ALLOYS

研究了银铜合金及添加微量稀土的银铜合金在400～750℃相对静止的空气中氧化动力学曲线,试验曲线与数学模型y^n=Kt拟合较好,式中常数K反映材料氧化初期表面膜的生成和厚度,常数n描述氧化过程中氧化速度衰减规律.微量稀土元素能显著地影响银铜合金高温氧化模型中的常数K和n,其中含钇的银铜合金的K值最小且n值最大,是优良的高温抗氧化材料.

The oxidation kinetic curves of Ag-Cu alloys and those with rera-earth elements at 400～750℃ and in relative stationary air are studied.These results are well in agreement with the mathmatic model, y^n = Kt. where the constant K describes the formation of the surface film at the primary stage of oxidation and its thickness, and n represents the decay of oxidattion rate.It is shown that the addition of rare-earth elements in Ag-Cu alloys has obvious effects on the values of K and n, especially for the Ag-Cu-Y alloy, which has the lowest value of K and the largest vaule of n, This alloy can be use for a high-temperature oxidation-resistant material.