Technology Research On Double-wire Welding Of T2 Copper And 1Cr18Ni9Ti Stainless Steel

The paper mainly introduced a processed research about the double wire welding of T2 copper and 1Cr18Ni9Ti stainless steel by the SATRMATC R450 automatic double-wire welding equipment. The combinations of welding stick are F 1.0mm copper (HS211) wire with stainless steel(H0Cr19Ni12Mo2) wire and copper(HS211) wire with low alloy steel(ER50S-6) wire. The copper and stainless steel plates achived bettter docking by adjusting appropriate parameters, slave wire taking pulse model and regulating distance to copper side, etc.By orthogonal experimental and extreme value analysis, the optimum parameters are obtained. In the case of adoppting copper wire and stainless steel wire, the copper wire is applied to master engine, with the voltage of 23.8V, current of 138A.While stainlee steel wire with pulse is applied to slave engine, the voltage is 24.2V, current is 118A, separation of plates is 2mm, welding speed and the bottom of the grave spacing are 50cm·min-1 and 1.5mm respectively.When master wire is copper and slave wire is low alloy steel, the voltage and current of master wier are 24.4V and 145A, while the slave wire with pulse are 23.6V and 124A, the welding speed is 55cm·min-1 and the bottom of grave spacing is 2mm. Above the two processes, the weld joints of high quality are achieved successfully without pores, cracks, inclusions and other defects.Mechanical property testing results show that the hardness of joint welded by copper wire and low alloy steel wire ranged from 90.6HB to 98.5HB, while the other one is 94.8～112.8HB. Tensile strength of the both joints reached more than 210MPa,and the fracture position is located in the welding heat affected zone of copper.The structure and composition distrution of the weld is dectected by XRD and EDS, The structure of the joint welded by copper wire and stainless steel wire is a-Cu and (γ+d)-Fe, the other one existing in the form of (a-Cu+F) two phase solid solution. The composition of the joint welded by copper wire and low alloy steel wire is distributed more evenly, the copper content in the weld zone ranges from 53.03% to 58.59%, closed to the theoretical value. The two joints has reached a relatively good fusion on both sides of the copper and stainless steel plate.