Optimization of Tensile Strength in Automated Shielded Metal Arc Welding Using Taguchi Technique

Abstract

The shielded metal arc welding (SMAW) is commonly used to weld for similar and dissimilar metals in the manufacturing fields. However, SMAW is a manual metal joining processing technique, the low welding quality and welding speed accuracy are both the main problems when using SMAW. So for a better result, the automatic based shielded metal welding (ABSMAW) was used to weld mild steel plates AISI1018 as the different electrode parameters in this study. The parameters focus on welding speed range from 3.19 mm/s to 4.6 mm/s and welding angle range from 45° to 60° by manipulating the electrode diameter from 2.6 mm to 4.0 mm for the welding process. The workpieces were clamped at the flat position in a customized jig for welding and all samples were cut with ASTM E8 standard before starting the tensile test. The tensile testing performed with the Huang Ta H500 universal testing machine which has the capability of 500 kN. The ABSMAW machine not only supports welding speed accuracy and smooth welding but also allow the better quality. The test result was analyzed with the Taguchi method while the result shows the welding angle is the most significant value for the tensile testing. The experiment found that there is an inverse relationship between welding angle and tensile strength means the welding angle increases then the tensile strength decreases dramatically also found out that there is the direct variation found in tensile strength welding speed and electrode diameter mean when the welding speed and electrode diameter increase, the tensile strength increases. The optimum values for tensile strength were produced by welding speed of 4.6 mm/s, welding angle of 45° and electrode the diameter of 3.2 mm.