Mechanical strength of AISI 304L stainless steel welded joints using GMAW and SMAW processes with different consumables

Abstract

Oxidation during welding processes is a determining factor in the quality and mechanical performance of the produced joints, especially in sensitive materials such as 304L stainless steel. This study aims to analyze the influence of oxidation on the mechanical strength of welded joints using MIG/MAG (GMAW) and SMAW processes, highlighting the microstructural effects and surface alterations that occur during welding. 304L stainless steel was chosen due to its wide application in the chemical, food, and petrochemical industries, as well as its good corrosion resistance. However, exposure to welding heat and atmospheric oxygen can cause the formation of surface oxide layers, directly affecting the mechanical properties and integrity of the joint. The consumables used, such as wires and electrodes of classes 308, 309, and 310, were addressed, along with their chemical and microstructural characteristics. The analysis includes technical standards for tensile, hardness, and impact testing, correlating the presence of oxidation with potential reductions in strength and increased susceptibility to intergranular corrosion. It is concluded that proper control of gas shielding, surface cleaning, and welding parameters is essential to minimize oxidation and ensure the mechanical performance of welded joints in 304L stainless steel.