Prediction of bead geometry parameters in MIG welded stainless steel 409L plates by mathematical modelling Rishabh Narang ⇑ , Vibhu Maheshwari, Pradeep Khanna Department of Manufacturing Processes and Automation Engineering, Netaji Subhas University of Technology, New Delhi 110078, India article info Article history: Received 20 September 2020 Received in revised form 21 October 2020 Accepted 27 October 2020 Available online xxxx Keywords: GMAW Bead geometry Mathematical equation Response surface methodology ANOVA abstract Metal inert gas (MIG) welding is considered to be a preeminent welding process due to its compatibility towards adapting automated applications in fabrication works. In present investigation, butt joint weld- ing was performed on ferritic stainless-steel plates of grade 409L in order to predict weld bead geometry parameters. Weld bead geometry influences the mechanical strength of the joint; therefore it must be of desired dimensions. It has been found that bead geometry depends upon the value of input parameters. Therefore, to obtain a sound weld joint, it is essential to determine the best combination of input param- eters. An attempt is made to establish a mathematical relationship between the input and response parameters and the response parameters in this case are weld width (W), height of reinforcement (H) and depth of penetration (D). The mathematical equation was generated using Taguchi statistical tech- nique and the adequacy of the developed equation was examined using analysis of variance (ANOVA) approach. The design of experiments (DOE) method was employed to conduct the experiments in a methodical manner and response surface methodology (RSM) was used for graphical optimization. Weld bead geometry can be predicted accurately by selecting appropriate process parameter values determined by the generated models. Ó 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Confer- ence on Materials, Processing & Characterization. 1. Introduction MIG welding is a popular method for achieving coalescence of metals for industrial applications [1]. Due to its growing demand in automated welding systems, it plays an essential role in the sheet metal industry [2]. MIG welding input parameters have an impact on quality, productivity and cost of welding joints. In order to achieve a perfect arc all the welding parameters should be con- formity [3]. The chief factors which contribute to its widespread use for various industrial applications include multi position weld capability, high productivity, slag-free and strong welds [4]. Construction and manufacturing costs of steel structures is directly affected by weld bead geometry [5]. Weld geometry also shows significant effect on the load bearing capability of a welded joint, which determines the performance in real time service con- ditions [6]. Thus, it is essential to obtain optimum weld bead geometry in order to produce a weld with desired mechanical properties [7]. Bead geometry is itself governed by the selection of welding parameters which are wire feed rate (WFR), welding speed (S), voltage (V), nozzle to plate distance (NPD) and torch angle (h) [5]. Several studies in the past have made an attempt to develop statistical models in order to correlate the weld bead geometry with welding parameters; hence it is required to establish a metic- ulous relationship between them [7]. Present investigative work focuses on analyzing the influence of input parameters on various response parameters such as bead width (W), depth of penetration (P) and height of reinforcement (H) as depicted in Fig. 1 [2]. If an accurate model can be predicted for the relationship between the input parameters and the bead geometry then the required bead geometry can be obtained by adjusting the input parameters [8]. Statistical technique developed by Taguchi was employed to formulate the mathematical equation. Taguchi based DOE approach is used in order to obtain an economical solution for process design optimization projects [9]. A multi-response opti- mization model was used to develop a parametric combination to yield favourable bead geometry. The adequacy of the developed equation and computation of graphical analysis was done using ANOVA and RSM respectively [8]. https://doi.org/10.1016/j.matpr.2020.10.795 2214-7853/Ó 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Materials, Processing & Characterization. ⇑ Corresponding author. E-mail address: rishabhn.bt.17@nsit.net.in (R. Narang). Materials Today: Proceedings xxx (xxxx) xxx Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr Please cite this article as: R. Narang, V. Maheshwari and P. Khanna, Prediction of bead geometry parameters in MIG welded stainless steel 409L plates by mathematical modelling, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2020.10.795