Comparative Analysis of the Combined Effect of Input Parameters on Heat Input and Heat Affected Zone in TIG Welding

Abstract

The quality and integrity of welded joints is highly influenced by the optimal combination of the welding input parameters. Due to the rapidly changing scenario in the manufacturing industry, optimization of process parameters is essential for a manufacturing unit to respond effectively to the severe competitiveness and increasing demand for quality products in the market. An attempt is made to study the  effect of heat input parameters properties of Tungsten Inert Gas (TIG) welding process.  The application of the surface plot in the investigation of the combined effect of input parameters on heat input and heat affected zone was pursued in this study. The central composite design matrix was used to obtain data from sets of experiments. Mild steel coupons measuring 60mm x 40mm x 10mm were welded with tungsten inert gas welding process. This study developed a model using expert systems, such as Response Surface Methodology and Artificial Neural Network to optimize and predict weld heat input and heat affected zone from input parameter such as current, voltage and welding speed. With the data collected from twenty experimental runs in this study, the result from one Response Surface Methodology analysis shows that a current of 130.00Amps, voltage of 20.94V, speed of 0.48m/min will produce heat input of 0.64277Kj/mm and heat affected zone of 5.42078mm with a desirability of 0.962.