Strength and Microstructure Analysis on Acetylene Welding Against ST 37 and ST 42 Steels

Abstract

This study aims to analyze the effect of welding using Acetylene gas on the mechanical properties and microstructures of steel plates up to 1 mm. Welding is carried out by the Acetylene gas welding method using Rod electrodes with a variety of parameters including welding speed and gas mixture composition. The mechanical properties tested include tensile tests and hardness tests, while microstructure analysis is carried out to evaluate the effect of the welding process on the formation of microstructures in the weld zone and heat influence zone (HAZ). The tensile test results show that the tensile strength of the Acetylene weld joint is lower than the strength of the base plate, but still meets the minimum strength standards required for structural applications. The hardness test results showed a higher hardness value in the weld area compared to the base plate, which showed a microstructural change due to local heating in the welding process. Microstructure analysis shows that there are phase changes such as the formation of martensites in the region (HAZ), which can affect the mechanical properties of weld joints. Overall, this study provides an overview of the effect of the welding process with Acetylene gas on physical properties, namely tensile tests, hardness tests, and microstructures in 1 mm steel plate weld joints, most importantly for the evaluation of the strength and durability of welded joints in industrial applications.