微量Ce对2090合金—纯Al扩散系统中Cu扩散系数的影响

测定了含Ｃｅ２０９０合金－纯Ａｌ扩散偶中Ｃｕ原子的浓度分布曲线，用Ｂｏｌｔｚｍａｎ－Ｍａｔａｎｏ法计算了扩散系数。结果表明：微量Ｃｅ可使Ｃｕ的扩散系数下降。Ｃｕ的扩散系数与其在扩散偶中浓度分布及浓度梯度有关。在合金中添加０．４０％Ｃｅ与添加０．２３％Ｃｅ相比，两者降低Ｃｕ扩散能力的效果相近。

EFFECT OF Ce MODIFICATION ON Cu DIFFUSION COEFFICIENT IN DIFFUSION SYSTEM OF ALLOY 2090-Al

The concentration distribution curves for Cu in the diffusion couples of Cemodified 2090 alloy with pure Al under different diffusing conditions have been measured.The Cu diffusion coefficients have been calculated by Boltzman-Matano method. The resultsindicate that adding minor Ce in the alloy may reduce the Cu diffusion coefficients. The Cudiffusion coefficients relates to its concentration distributions and gradients in the diffusioncouples. In general terms, the effect of adding 0.40% Ce on the Cu diffusion rate is generallysimilar to that of adding 0.23% Ce in the alloy.