喷射成形7055铝合金薄板搅拌摩擦焊研究  

Study on friction stir welding of spray formed 7055 aluminum alloy sheet

作　　者：邱宇 孟强[1,2] 栾国红 曾元松[1] 李志强 张豪 QIU Yu;MENG Qiang;LUAN Guo-hong;ZENG Yuan-song;LI Zhi-qiang;ZHANG Hao(AVIC Manufacturing Technology Institute,Beijing 100024,China;Beijing FSW Technology Co.,Ltd.,Beijing 100024,China;Jiangsu Haoran Spray Forming Alloy Co.,Ltd.,Zhenjiang 212009,China)

机构地区：[1]中国航空制造技术研究院,北京100024 [2]北京赛福斯特技术有限公司,北京100024 [3]江苏豪然喷射成形合金有限公司,江苏镇江212009

出　　处：《塑性工程学报》2020年第7期117-122,共6页Journal of Plasticity Engineering

摘　　要：针对1.2 mm厚喷射成形7055-T74铝合金薄板,开展搅拌摩擦焊对接的正交试验。以焊缝成形质量和接头性能为评价依据,优化搅拌头和焊接工艺,并对优选条件下的焊接接头微观组织和显微硬度进行分析。结果表明,当选用轴肩直径为Φ8 mm、轴肩形貌为双圆环的搅拌头和旋转速度为800 r·min^-1、焊接速度为200 mm·min^-1的焊接工艺参数时,焊缝表面无缺陷,内部质量满足HB/Z 416标准I级焊缝要求;焊接接头的抗拉强度为495.7 MPa、达到母材的83.5%,断后伸长率为4.47%,拉伸断裂发生在后退侧,拉伸断口具有韧性断裂的特征;热机影响区组织发生拉长弯曲,焊核区发生了再结晶,组织为更加细小的等轴晶;焊接接头的硬度分布曲线近似于"W"形,硬度最高点在焊核区,最低点在后退侧的热影响区。The orthogonal test of friction stir welding butt was carried out for spray formed 7055-T74 aluminum alloy sheet with thickness of 1.2 mm.Taking the forming quality of weld and the joint performance as evaluation basis,the welding tool and welding process were optimized,and the microstructure and microhardness of the welded joint under optimal conditions were analyzed.The results show that when the welding tool with the shoulder diameter ofΦ8 mm,the shoulder morphology of double ring,and the welding process parameters with the rotation speed of 800 r·min-1 and the welding speed of 200 mm·min-1 were used,the weld surface has no defects and the internal quality meets the requirements of grade I in HB/Z 416 standard.The tensile strength of the welded joint is 495.7 MPa,reaching83.5%of the base metal,and the fracture elongation is 4.47%.The tensile fracture occurs at the retreating side,and the tensile fracture shows the characteristics of ductile fracture.The structure of the TMAZ is elongated,and recrystallization occurs in the nugget zone(NZ),and the structure is finer equiaxial grain.The hardness distribution curve of the welded joint is similar to"W"shape,with the highest point of hardness in NZ and the lowest point in heat affected zone(HAZ)of the retreating side.

关 键 词：喷射成形 7055铝合金 搅拌摩擦焊 微观组织 力学性能 

分 类 号：TG453.9[金属学及工艺—焊接]