厚板7022铝合金搅拌摩擦焊接实验研究

Experimental study on friction stir welded on thick plate of 7022 aluminium alloy

对10mm厚度的7022铝合金进行了搅拌摩擦焊接,获得表面光滑的焊接接头,并通过X射线检测焊缝无裂纹和气孔。研究该搅拌摩擦焊接头不同区域的显微组织特征,并通过拉伸、冲击和硬度试验分析了焊接接头的力学性能。结果表明,焊缝处组织为细小均匀的等轴晶粒;在搅拌头转速为400r/min,焊接速度为100mm/min时焊接接头的抗拉强度、屈服强度均比母材高;焊接接头的冲击韧性比母材高;焊接接头显微硬度比母材稍低,焊接接头具有良好的力学性能。

Experimental study is carried out on the friction stir welding of 10mm thick 7022aluminium alloy.The welded joint with smooth surface had been obtained.No welding crack and pore have been discovered by X-ray detection.The microstructure of friction welded joint is studied in different regions.The mechanical properties of welded joints are analyzed through tensile,impact and hardness tests.The results show that the organization of welded joint is small homogeneous isometric crystal.The tensile strength and yield strength of friction stir welded joints of 7022 aluminium alloy excess these of the base material when the rotating speed is 400r/min and the welding speed is 100mm/min.The impact toughness of welded joint is higher than the base material.The microhardness of welded joint is slightly lower than the base material.Welded joint has good mechanical properties.