Researching varieties in welding bead caused by shielding gas mixture rates and guiding types in gas metal arc welding

The effect of welding wire and shielding gas type in gas metal arc welding on weld metal composition and mechanical properties is very significant. Today, in order to take advantage of positive features of different shielding gases and improve the benefit that will be gained from the shielding gas, mixture of shielding gases is used. The idea of supplying shielding gases independently and concentrically by alternative means and supplying shielding gases in double channel gas metal arc welding torch without mixing, has been studied by some researchers. It has been thought that mechanical and physical properties that are demanded from weld metal might be satisfied by feeding expensive inert gases in a little amount but sufficiently, to obtain desired arc characteristics and using cheap shielding gases to block the interaction of the arc with its surrounding atmosphere. Besides research in conventional gas metal arc welding process, some researchers have studied gas metal arc processes in which shielding gases are supplied alternatively and reported the differences of these processes in some aspects compared to conventional gas metal arc welding. In supplying shielding gases alternatively and double channel shielding gas supply in MIG/MAG welding studies, arc transfer modes, strength and toughness of weld seam, porosity in weld seam, spatter loss in inner and outer nozzles, welding speeds and macrographs of weld seams have been evaluated. In this study, double channel gas metal arc welding torch has been designed and manufactured. Base metals that will be used in this study are S235JR low carbon steel and X2CrNi189 austenitic stainless steel. Welding will be carried on these materials with solid, flux and metal cored wires not only with mixtures gases using torch but also double channel torch and after that strength of weld metal, angular distortion of the welding assembly will be measured. In addition to that, the differences between these two processes will be introduced by macro and micro examination of weld metal and HAZ and the results will try to correlate temperature data that will be obtained from a thermal camera. Furthermore, cost analyses for double channel shielding gas guiding process and conventional mixture gas process will be realized and cost differences between these two processes will be introduced perceptibly.