| 2007 №04 (02) | 2007 №04 (04) |
The Paton Welding Journal, 2007, #4, 9-16 pages
Study on the effect of pulsed GTAW process parameters on bead geometry of the AISI 304l stainless steel welds
P.K. Giridharan1, N. Murugan2
1Amrita Institute of Technology, India2Coimbatore Institute of Technology, India
Abstract
A study on the effect of pulsed gas tungsten arc welding (GTAW) parameters on weld bead geometry was carried out for welding of the 304L stainless steel sheets of 3 mm thickness. Autogenous welding with square butt joint was employed. The advantages of pulsed GTAW process, such as controlled heat input, increased depth to width ratio and less distortion etc., can be achieved only when the welding parameters were thoroughly studied, controlled and optimized through mathematical models. Hence, mathematical models were developed correlating the important controllable pulsed GTAW process parameters like pulse current, pulse duration and welding speed with weld bead parameters, such as penetration, bead width, aspect ratio and bead area of the weld. A design of experiments based on central composite rotatable design was employed. The developed models were found to be adequate based on regression and ANOVA analysis. The models were validated by plotting scatter diagram and by conducting confirmation test. Weld bead parameters predicted by the models were found to confirm with observed value with high accuracy. Using these models, the main and interaction effects of pulsed GTAW parameters on weld bead parameters can be studied. Optimization of the process parameters was also carried out to obtain optimum bead parameters using quasi-newtonian numerical optimization technique. Results of the optimization were also presented in this paper.
Keywords: pulsed GTAW process, welding of stainless steel sheets, mathematical models, design of experiments, ANOVA analysis, optimization
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