喷射成形7475铝合金FSW工艺与性能

Friction-stir welds(FSW) of spray formed 7475 aluminum alloy plate

采用搅拌摩擦焊(FSW)方法对厚度为4 mm的喷射成形7475铝合金进行了焊接工艺及性能研究,通过优化搅拌头的形状和尺寸,调整焊接工艺参数得到了表面成形良好的焊接接头,经过力学性能测试和微观分析.结果表明,当焊接工艺参数选择合适时,可得到外形美观、无缺陷的焊缝;如果工艺参数选择不当,则会出现沟槽、飞边和隧道形缺陷;还发现焊接接头力学性能与焊接工艺参数存在一定的关系,在旋转频率为1 200 r/min,且焊接速度为80 mm/min时,可以获得较好的焊接性能,抗拉强度可以达到442 MPa.

Friction-stir welds(FSW) of spray formed 7475 aluminum alloy plate with 4 mm thickness were studied.The shapes and dimensions of FSW tools as well as welding parameters were optimized based on mechanical tests and micro-analysis.Experimental results show that good-appearance welds can be achieved by optimal welding parameters.However,fin and groove defects appear if the welding parameters are not appropriate.It also shows that the mechanical properties of the joints are affected by the welding parameters.Some relations between the mechanical properties and the welding parameters were established.As the rotating speed is 1 200 r/min and the welding speed is 80 mm/min,the good weld is achieved and the tensile strength of the weld reaches 442 MPa.