PULSED MIG WELDING OF AL-ZN-MG ALLOY

Pulsed MIG welding of Al-Zn-Mg alloy has been carried out by using extruded sections of base material and Al-Mg(5183) filler wire. During welding the pulse parameters such as the mean current and pulse frequency are varied and their effect on the microstructure and geometry of weld deposit, hardness of weld deposit and the tensile properties of the weldment have been studied. Weldments are also prepared by using a conventional continuous current MIG welding process, where the welding currents equivalent to that of mean currents of a pulsed process are used. The properties of the weldments prepared by the conventional MIG process are compared with that prepared by the pulsed current process. The properties of weldment are found to be affected by the geometry of weld deposit which is governed by the pulse current parameters. However, the use of pulsed current has been found to improve the mechanical properties of weldment. © 1990, The Japan Institute of Metals. All rights reserved.