摘要
介绍了微型剪切试验的基本原理和试验过程,进行了6061铝合金搅拌摩擦焊接接头的微型剪切试验,同时测试焊接接头的拉伸强度,观察接头的金相组织。试验表明6061铝合金搅拌摩擦焊接接头各个区域的力学性能不均匀,热机影响区的剪切强度最差,仅为母材的65%,低于宏观焊接接头的79%,热机影响区压入率最低,其次是热影响区。结合接头的微观组织和Al-Mg2Si伪二元相图发现,该区强化相Al-Mg2Si的聚集和张大是该区域为焊接接头的薄弱区域的关键原因。焊核区细小的等轴晶粒状态是该区域剪切强度和压入率高的主要原因。
The basic principle of mini-shear-test（MST） and test process is introduced.The MST of the friction stir welding （FSW） joint of 6061 Aluminum is carried out. Meanwhile, the joint＇s tensile strength is tested.The metallographic organization is observed.The result shows that the mechanical inhomogeneity of the 6061 aluminum alloy FSW joint is quite obvious.The shear strength of the thermal-mechanical affected zone is the worst,which reaches only 65% of the body mental and less than 79% of the macro-joints. The pressed-into-rate of the zone is the lowest,followed by that of the heat affected zone （HAZ）.Combined with the microstructure observation and the AI-Mg2Si pseudo binary phase diagram,the shearing strength and pressed-into-rate of the different area of the FSW joint is analyzed.Microstructure is the main reason which leads to the change of the properties.
出处
《电焊机》
北大核心
2012年第10期92-95,共4页
Electric Welding Machine
基金
中央高校科技创新基金资助项目(A0920502051001-331)
