7075铝合金不同冷却介质条件下搅拌摩擦焊接头的组织与性能

7075铝合金不同冷却介质条件下搅拌摩擦焊接头的组织与性能 Microstructure and property of 7075 aluminium alloy weld joint by FSW 汪虎 WANG Hu 1 first-author 韦叶 WANG Wei 1 王巍 WEI Ye 1 黄廷尊 HUANG Tingzun 1 周礼龙 ZHOU Lilong 1 航天工程装备(苏州)有限公司 航天工程装备(苏州)有限公司 Aerospace Engineering Equipment (Suzhou) Co.,Ltd. Aerospace Engineering Equipment (Suzhou) Co.,Ltd. 针对3 mm厚的7075铝合金板材,采用相同的焊接参数分别在空气和水中进行搅拌摩擦焊接(FSW),研究不同冷却介质对接头的热循环曲线、宏观形貌、微观组织、硬度以及力学性能的影响。结果表明,水下焊接的热循环曲线更趋于平缓,高温停留时间短,焊缝表面成形更好,焊核区(NZ)和热影响区(HAZ)显微组织的晶粒更细小,接头热影响区更窄,并且接头的塑性流形更清晰,而空气中焊接的接头热影响区软化严重,硬度仅为113 HV。水下FSW接头断裂形式为脆性断裂,而空气中FSW接头断裂形式为韧性断裂。 The spray forming 7075 aluminum plates with thickness of 3 mm were welded by friction stir welding（FSW）using the same welding parameters under different media. The effects of different media on the joint of the thermal cycle curve,macro morphology,microstructure,hardness and mecha-nical properties were discussed. The results show that the thermal cycling curve of underwater welding tends to be more smooth and high temperature residence time is shorter. The weld surface of the underwater welding is forming better than that formed in the air. The grain of underwater joint is finer and the heat affected zone is narrow with clearly plastic manifold. The heat affected zone of under-air joint is softening seriously which hardness is only 113 HV. The fracture form of underwater joint is dissociation fracture,while the welded joint in air is fracture of quasi dissociation. 7075铝合金 搅拌摩擦焊 热循环 微观组织 力学性能 7075 aluminum alloy friction stir welding thermal cycling microstructure mechanical properties TG453.9 2022-03-08 1 50