Mathematical modelling for prediction of angular distortion in the MIG welded Aluminium 6101 plates

Abstract

Metals are commonly joined using the Metal Inert Gas (MIG) which is also known as the Gas Metal Arc (GMA) welding process in the fabrication industries because of their ability to weld an extensive diversity of metals as well as its alloys and composites. It can also get fully automated which makes it appropriate for mass fabrication. In this process, like other arc welding operations, there is a huge amount of heat input into the workpiece due to which there are rapid and non-uniform heating and cooling cycles involved. This results in the thermally generated stresses transverse to the weld due to which angular distortion is very likely to get introduced. The important input parameters which contribute significantly to the angular distortion are found to be voltage (V), torch angle (TA), wire feeding rate (WFR), nozzle-to-plate distance (NPD) and welding speed (WS). In the present work, the analytical method of design of experiments (DoE) is utilized to develop a mathematical model relating these with the angular distortion on the Aluminium 6101 plates. The fitness of the representation is scrutinized using the ANOVA technique. The graphical representation of the direct and the interactive consequences of input variables on the angular distortion is evolved by utilizing the response surface methodology (RSM) approach.