Experimental Investigation and Optimiztion of Welding Parameters of Metal Inert Gas Welding Process in Joining Dissimilar Metals

The erection and production industries of modern world use dissimilar metals for different parts that are primarily joined using numerous welding processes. Metal Inert Gas welding has a wider application in the manufacturing sectors. As such in machining, optimization of welding parameters must be done to increase the productivity and maintain excellent weld strength. The welding strength which is a function of hardness of the joint is major criteria that determine the life of the welded joints. AISI 1045 alloy steel and High Chromium high carbon steel was welded. Welding current, voltage and the pressure of the inert gas are varied with welding time and hardness of the weld being the responses. Grey Relational Analysis has been used to identify the most feasible combination of parameters based on the Grey Relational Grade where it converts the original values into reference values. The suitable welding parameters were found to be 26 volts of voltage, 200 amperes of welding current and 6 bar of pressure. Technique for order of preference by similarity to ideal solution has shown that the optimal solution based on the preference number is 22 Volts, 150 amperes and 4 bar.