为评价搅拌摩擦焊(FSW)构件的可时效成形性,对7075铝合金FSW构件固溶处理后进行时效成形工艺,试验研究了固溶处理影响下FSW构件时效成形后构件性能的变化规律.试验结果表明,固溶处理后时效成形工艺有助于提高FSW构件的抗拉强度、延伸率和电导率.固溶处理后180 ℃时效成形时,FSW试样抗拉强度峰值显著提高,达到449.4 MPa,是仅时效成形工件抗拉强度的139.5%,为原始焊接试样抗拉强度的1.4倍,此时焊件延伸率达到峰值4.2%,固溶处理对试样延伸率有一定的提升作用.微观结构观察结果表明,固溶处理的引入对FSW构件时效成形过程焊缝区特征组织产生显著影响,有助于消除焊缝的不均匀组织特征的影响,从而有利于成形试样的性能均匀化和提高.%To evaluate the age formability of the friction stir welded(FSWed)structures, the influence of solid solution treatment on the mechanical properties of FSWed 7075 aluminum alloy parts were investigated during a sequential process of solid solution and aging forming. The results show that the involved sequential process is beneficial for the improvement in the tensile strength,elongation and conductivity of the workpiece. Especially,for 180 ℃ aging temperature of,the tensile strength of FSWed samples is significantly improved, and reaches up to 449.4 MPa, which is 139.5% of that part only involved age forming, and 40% higher thanthe initial welded parts. The elongation of the welded parts reaches a maximum value of 4.2% during the combined process. The solid solution treatment causes a siligh enhancement in the elongation. Microstructural observations indicate that the solid solution treatment exert a crucial role on the microstructure of the FSWed joints. The solid solution treatment facilitates can effectively eliminate the influence of the inhomogeneous texture of the welded parts,and thus facilitate the homogenization and improvement of their performance.
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