Experimental Investigation of TIG-welded AISI 1008 Carbon Steel

TLDR: In this paper, the influence of TIG welding process parameters on the mechanical and microstructural properties such as tensile strength, hardness, and microstructure of AISI 1008 carbon steel was evaluated.

Abstract: Carbon steel is widely used in engineering applications due to its exceptional mechanical properties, and low cost. The fabrication technique employed to weld carbon steel plays a vital role in the final performance of the welded component when put into service. TIG welding is a generally accepted arc welding technique due to its ease and versatility coupled with its capacity to produce high-quality welds. It is the most desirable technique employed for welding plain carbon steel. This work aims to evaluate the influence of TIG welding process parameters on the mechanical and microstructural properties such as tensile strength, hardness, and microstructure of AISI 1008 carbon steel. The process parameters considered in this work were the TIG welding current, and gas flow rate. The tensile testing and the Vickers hardness testing have been carried out for the welded samples. The microstructural investigation was also carried out for the fusion zones (FZ) and the heat-affected zones (HAZ). The test results were analyzed, and emerging properties were compared for the various set of parameters. Welded specimen produced with 140 A, 15 L/mm had the highest hardness value. However, the highest average ultimate tensile strength of 432.89 MPA was produced from process parameters 180 A, 19 L/mm. Finer grain structures were seen in the fusion zones as compared to the heat-affected zones for all selected parameters.