Influence of Current Intensity and Shielding Gas in GMAW of DH36 Grade High Strength Steel

In this study, DH36 high strength steel plates having 12 mm thickness were joined by welding wire (EN 758: T46 4 M M 1 H5) in gas metal arc welding technique.Shielding gas compositions were selected as 100% argon and 20% CO2+ 80% argon gas mixture in order to investigate the effect of CO2 on mechanical properties.The welded joints were prepared at 170 A, 24 V; 190 A, 27 V, and 210 A, 30 V welding parameters.Tensile strength, the Charpy impact tests, microstructure of welded materials and their microhardness distribution throughout joining were determined.Micro and macrostructure photos and scanning electron microscopy micrographs of specimens were obtained.This study investigated the effects of current intensity on microstructure and microhardness distribution of transition zone between DH36 high strength hull steel and gas metal arc welding joint.The optimum parameters were advised to users at the end of this study.