工艺参数对Mg-3Zn-0.5Y合金搅拌摩擦焊接接头组织与性能的影响

Effect of welding parameters on microstructures and properties of Mg-3Zn-0.5Y alloy joint by FSW

采用搅拌摩擦焊对Mg-3Zn-0.5Y合金板材进行焊接,获得了成型较好、无缺陷的焊缝,研究了工艺参数对焊接接头显微组织及力学性能的影响。结果表明,当焊速为110 mm/min时,转速在600~1 300 r/min范围内能够得到成型良好的焊缝,随着转速的升高,接头强度先升高后减小;当搅拌头旋转电机转速为1 100 r/min时,焊接速度在90~110 mm/min范围内能够获得成型良好的焊缝,随着焊接速度的提高,接头强度先提高后减小。拉伸断裂方式主要为韧脆混合断裂。当搅拌头旋转运动速度为1 100 r/min、焊速为110 mm/min时,Mg-3Zn-0.5Y合金焊缝综合力学性能较优,拉伸强度达到222.5 MPa。

In this paper,the Mg-3Zn-0.5Y alloy weld in good shape and defect-free was produced by friction stir welding,and the influence of welding parameters on the microstructure and mechanical properties of the welded joint was studied.As a result,when the welding speed is 110 mm/min,the well-formed weldcan be obtained with the rotation rate at 600~1300 r/min.The tensile properties of the joints first increase and then decrease in the range.When the rotational speed of 1100 r/min,the well-formed weld can be obtained with the rotation rate at 90~1300 mm/min.With the increase of rotating speed,the joint strength increases first and then decreases.Brittle fracture and ductile fracture can be observed simultaneously.Good comprehensive mechanical properties can be obtained when the rotation rate was 1100 r/min and the welding speed was 110 mm/min,the tensile strength was 222.5 MPa,the yield strength was 173.8 MPa.