送丝速度对6061铝合金CMT焊接接头性能的影响

Effects of Wire Feeding Speed on Properties of CMT Welded Joints of 6061 Aluminum Alloy

以ER5356焊丝为填充金属,6061铝合金板材为母材,进行了冷金属过渡焊接(CMT)试验。通过改变焊接时的送丝速度而得到不同的焊接试样,对其微观组织和力学性能进行了观察测试。结果表明,6061铝合金经CMT焊接后热影响区宽度相对MIG焊较小,热影响区的晶粒粗大,硬度值最低,大约为45 HV;焊接的四组试样最大的抗拉强度为192.8 MPa,是母材抗拉强度的78.4%。

Taking ER5356 wire as filler and 6061 aluminum alloy as base metal, cold metal transfer （CMT） welding experiments were carried out. Weld samples were prepared by changing the wire feeding speeds. The mechanical properties and microstructure of the samples were observed and tested. The result show that the heat affected zone （HAZ） width of 6061 aluminum alloy after CMT welding is relatively narrower than that of MIG welding. The grains of HAZ are coarse, and the hardness of HAZ is the lowest （ about 45 HV）. The maximum tensile strength of four groups of welding samples is 192.8 MPa, which is 78.4% of the parent metal.