Experimental investigation of process parameters of cold metal transfer welding-based wire arc additive manufacturing of aluminum 4047 alloy using response surface methodology

Abstract

Proper parameter selection is crucial for obtaining the required shape of the beads and reducing defects like uneven welds, cracks, porosity, and irregularities while creating wire arc additive manufacturing (WAAM) samples. This study aims to investigate the impact of three input process parameters (current, welding speed, and gas flow rate) at three different levels on the properties (weld bead width, bead height, and dilution) of samples made from aluminum 4047 using the CMT-WAAM process. The study will analyze the data using response surface methodology (RSM). A central composite design (CCD) matrix was employed to develop a design of experiment incorporating three process factors. The appropriateness of the design was assessed by ANOVA analysis. The upper limits for the height and penetration of the weld bead were 2.83 mm and 3.12 mm, respectively. The lowest level of width measured was 9.44 mm. The forecasted ideal input parameters were a current of 150 A, a welding speed of 50 cm/min, and a shielding gas flow rate of 15 l/min. The findings demonstrated that the current exerted the most significant impact on determining the various responses, with welding speed and gas flow rate being the subsequent influential factors. The microstructures were analyzed using optical microscopy, revealing that the microstructure of the wall region comprised columnar and equiaxed grains. This study has considerable potential for manufacturing aluminum items utilizing a CMT-based arc welding technique.

Graphical Abstract