6xxx系铝合金材料中厚板搅拌摩擦焊工艺研究

Research on Friction Stir Welding Process of Medium and Thick Plates of 6xxx Series Aluminum Alloy Materials

为了获取6xxx系铝合金材料中厚板搅拌摩擦焊的最佳工艺参数,在不同的参数下对10mm厚6xxx铝合金中厚板进行搅拌摩擦焊接进行了实验对比研究,确定出最佳工艺参数:搅拌头旋转速度800r/min、焊接速度100mm/min、搅拌头仰角3o。经过对焊接接头显微组织与力学性能的分析:抗拉强度平均值为319MPa,达到了母材的84.8%,伸长率平均为11.3%;断口形貌均为韧窝型断口,断裂性质属于韧性断裂;焊缝中心的显微硬度达到50HV,焊缝中心到母材之间存在软化区,硬度最低为45HV,焊接接头质量良好。文章针对铝合金搅拌摩擦焊工艺展开研究,为其在工业生产应用中提供了重要工程实践参考。

In order to obtain the best process parameters of friction stir welding of medium and thick plates of 6xxx series aluminum alloy materials,the friction stir welding of 10-mm-thick 6xxx aluminum alloy medium and thick plates is experimentally compared under different parameters,and the best process parameters are determined:the rotation speed of the mixing head is 800 r/min,the welding speed is 100 mm/min,and the elevation angle of the mixing head is 3°.After the analysis of the microstructure and mechanical properties of the welded joint,the average tensile strength is 319 MPa,reaching 84.8%of the base material,and the average elongation rate is 11.3%.The morphology of the fractures are nest fractures,and the fracture nature is ductile fractures;The microhardness of the welding seam reaches 50 HV,there is a softening zone between the welding seam and the base material,the minimal hardness is 45 HV,and the quality of the welded joint is good.This paper studies the friction stir welding process of aluminum alloy,which provides an important engineering practice reference for its industrial production application.