Joining of Dissimilar Material Using Gas Metal Arc Welding

Joining of thin sheet metals by welding was once said to be difficult as it usually burns through hole at the base metal. High welding temperature exerted on the base metal lead to cause undesirable distortion. Further challenges on joining of dissimilar materials by using fusion welding are when both base metals have different melting temperature and also might lead to breakdown of their mechanical properties. This research objective was to study the weldability of dissimilar selected metals sheet namely mild steel and galvanized iron. It was to determine the suitable welding parameters to join both metals sheet with thickness of 1.0 mm, each. Two welding parameters identified as the welding current with a range of 34.0 – 55.5 A and wire feed speed ranging from 2.0 – 4.0 m/min, the Gas Metal Arc Welding (GMAW) process was thus employed. The samples were later tested for its tensile strength in order to get the safe welding parameter that could meet the tensile strength of the joint. It was determined that the range of safe GMAW welding parameters for both metals was 44.9 – 55.5 A of the welding current and 3.0 m/min wire feed speed.