Cu／Al真空扩散焊接显微组织分析

采用真空扩散焊工艺方法，对Cu与Al扩散焊接头的组织性能进行了试验，利用扫描电镜（SEM）、电子探针9EPMA）、显微硬度等测试焊接过渡区及基体组织和性能进行了分析。试验结果表明：采用真空扩散焊工艺，在加热温度530－540℃，保温时间60min，压力11．5MPa时，在Cu/Al界面处形成明显的扩散过渡区，扩散区域宽约40μm。在铜侧过渡区中产生金属间化合物，会出现显微硬度高峰区，控制Al的扩散浓度可避免或减少界面处金属间化合物的产生。

Microstructure analyses in vacuum diffusion weldedjoint of copper and aluminum

By using vacuum diffusion welding process, the microstructures and performance of diffusion transition zone for the Cu/Al diffusion welding joint were researched by means of SEM, EPMA and micro-hardness test. The results indicate that under the condition of 520～540?℃ in holding time 60?min and pressure 11.5?MPa, the diffusion joined interface is obviously produced between copper and aluminum. The width of the diffusion interface zone is about 40?μm. The micro-hardness peak zone is formed in the copper side of the joined interface because of metal compounds such as γ and β phase. By controlling the Al diffusion amount, the brittle intermetallic compounds can be avoided or decreased.