Non-linear modeling of mechanical properties of plasma arc welded Inconel 617 plates

Abstract

Abstract In the present research paper, an attempt is made to perform non-linear modeling of the plasma arc welding (PAW) of Inconel 617 plates with the help of experiments conducted using a central composite design of experiments (CCD). It is to be noted that the PAW is a high depth to width ratio welding process that can be used to join high strength materials like Inconel 617. Furthermore, mechanical properties such as ultimate tensile strength (UTS), percentage of elongation, flexural strength and hardness of the welded joints are highly dependent on the conditions under which the welding is performed. In the present paper, the weld current, weld speed and plasma gas flow rate of PAW are considered as input process parameters to study the effect of these variables on the above mentioned mechanical properties. Industrial pure argon (99.99 %) is used as both plasma and shielding gas during the welding of the 2 mm thick Inconel 617 plates. Surface plots and analysis of variance (ANOVA) are used to test the statistical adequacy of the models. Moreover, the prediction accuracy of the models is tested with the help of experimental test cases and found to be in good agreement.