U-10Zr/Zr-4合金界面的微观结构及生长动力学研究（英文）

Microstructural Characterization and Growth Kinetics of the Reaction Layer in U-10wt% Zr/Zircaloy-4 Diffusion Couples

为研究U-Zr合金与Zr-4合金之间的相容性和扩散行为,采用真空热压扩散法制备U-10wt%Zr/Zr-4扩散偶,随后在高真空中580~1100℃高温热处理样品。采用扫描电镜和透射电镜分析检测扩散偶的界面微观结构和元素分布。系统研究了两种合金之间的相容性。δ-UZr_2层和厚约20nm的富铀层形成于热压扩散法制备的样品界面。测量了合金界面扩散系数常数和扩散激活能,分别为(4.23±0.63)×10^(-6)m^2/s和(160.73±1.67) kJ/mol。结果表明U-10wt%Zr/Zr-4扩散偶的扩散系数大于U-Zr合金的,特别是在低温段。

To investigate the compatibility and diffusion behavior between U-Zr alloys and Zr-4 alloys,solid-to-solid U-10 wt% Zr/Zr-4 diffusion couples were assembled by vacuum hot pressing and then annealed under vacuum at temperatures ranging from 580 ℃ to 1100 ℃ for various time.Scanning and transmission electron microscopes were employed to analyze the microstructures and composition profiles at the interfaces of the couples.The compatibility between the two alloys was investigated.δ-UZr2 and ~20-nm-thin U-rich layers existed in the vacuum-hot-pressed samples.The interdiffusion coefficient constant and activation energy are found to be（4.23±0.63）×10^-6 m^2/s and（160.73±1.67） kJ/mol,respectively.The interdiffusion coefficients of the U-10 wt% Zr/Zr-4 alloy couples are higher than those of U–Zr alloys,especially at low temperature.