显微组织特征
(1. 武汉大学 物理科学与技术学院， 武汉 430072;
2. Center for Robotics and Manufacturing Systems，
University of Kentucky，Lexington，Kentucky 40506，U.S.A.)
摘 要: 采用气氛保护钎焊工艺，对AA4343/AA3003铝合金复合板材料的钎焊接头组织特征，及其与焊接工艺的关系和对接头区显微硬度的影响进行了研究。实验结果表明，钎焊过渡区由单相α(Al)固溶体层和Si扩散层组成，它们的厚度随钎焊条件而发生变化。远离焊接区有一个α(Al)固溶体残余层，它的厚度保持20μm基本不变，与焊接参数和材料性质无关。讨论了钎焊接头特征组织的形成机理。
关键字: 铝合金；钎焊；显微组织；过渡区
AA4343/AA3003 Al-alloy sheet
brazed joints
（1.College of Physics Science and Technology，
Wuhan University，Wuhan 430072，China;
2.Center for Robotics and Manufacturing Systems，
University of Kentucky，Lexington，Kentucky 40506，U.S.A.）
Abstract:The metallurgical characteristics, relationships with welding conditions and influence upon microhardness of AA4343/AA3003 aluminum sheet brazed joints were studied by using atmosphere shielded brazing process. The results indicate that the transition zone of the joint consists of an α(Al) solid solution layer and a Si diffusion layer. The thickness of the transition zone varies with the welding conditions. In the part far from the fillet，the thickness of a “residual α(Al) solid solution layer” is nearlyconstant，around 20μm，which is independent of welding conditions and materials. The formation mechanism of the characteristic microstructures was discussed.
Key words: aluminum alloy; brazing; microstructure; transition zone
