钛/铝异种合金FSLW接头的成形与组织研究

Forming and Microstructure of Ti/Al Dissimilar Alloys FSLW Joint

以Ti-6Al-4V钛合金和7075-T6铝合金为对象,将钛合金作为搭接上板,研究了钛/铝异种合金搅拌摩擦搭接焊接头的成形与显微组织。结果表明,当搅拌头转速较高时,搭接界面处会产生因材料填充不及时而形成的孔洞缺陷;随着转速的降低,孔洞缺陷的尺寸逐渐减小,当转速为190 r/min时可获得缺陷极小的接头,连接界面处钛/铝合金结合良好。在本文所使用的焊接工艺中,整个焊接过程在β相变点以下进行。

Taking Ti-6 Al-4 V titanium alloy and 7075-T6 aluminium alloy as the research object, titanium alloy was used as the lap upper plate, the forming and microstructure of Ti/Al dissimilar alloys friction stir lap welding（FSLW） joint were studied. The results show that when the rotational speed of stirring head is high, void can be observed at the lap interface due to untimely filling of the material. With the decrease of the rotational speed, the size of void gradually becomes small. When the rotational speed is 190 r/min, the joint with very small defect can be obtained, and the titanium and aluminum alloys have good bonding at the interface. In the welding process used in this article, the whole welding process is under the β phase transition point.