铝合金阳极氧化薄膜热膨胀性能测试分析

介绍两种利用Ｘ射线测试铝合金阳极氧化薄膜热膨胀系数的原理和方法（阳极氧化薄膜通常由非晶态的Ａｌ２Ｏ３及部分晶态Ａｌ２Ｏ３组成）．一种方法为将氧化膜制成粉末，利用晶态Ａｌ２Ｏ３中衍射晶面的面间距和温度之间的线性关系导出Ａｌ２Ｏ３的热膨胀系数；另一种方法为测出一定厚度的整体样品（氧化膜和基体完整结合）中氧化膜中存在的热应力，利用相应的公式导出氧化膜的热膨胀系数．对两种方法得到的数值差异进行了分析．

Research on the Thermal Expansion Behavior of Anodic Films on Aluminium

The paper introduces the two principles and methods, which are based on the X ray diffraction for the measurements of thermal expansion coefficients of anodic films. Owing to the selected anodic films comprised of amorphous alumina and partial crystalline alumina, one way is to use the powders of anodic film and utilize the linear relationship between the lattice spacings of crystalline alumina and temperatures to infer the thermal expansion coefficients. The other way is that by measuring the thermal stresses existing in the anodic film of entire specimen, i.e. the film and substrate combining together, during temperature changes, the thermal expansion coefficients can be calculated by proper model and formula. And the data obtained by the two means are also analyzed.