Effect of Single Point Incremental Forming (SPIF) Process Parameters on Surface Roughness of Dissimilar Tailor Welded Blanks using the Taguchi Method

In the present paper, the Taguchi method is implemented to figure out which set of process parameters is optimal for forming dissimilar aluminum alloy blank joints together using friction stir welding. In single-point incremental forming (SPIF), four process parameters were taken into consideration: rotational speed, feed rate, step size, and wall angle. Measurements were made on both sides, inner and outer of each surface of the formed part due to dissimilar material of tailor welded blanks (TWBs) to see the pattern and relationship. The results show that step size is the most important parameter, then the wall angle. The rotating speed and feed rate had the least impact on surface roughness. The optimal parameters are a 0.2 mm step size, a 55-degree wall angle, a 1500 rpm rotational speed, and a 1000 mm/min feed rate for the inner and outer surfaces of AA5052. While the AA6061 gives the optimum values of 0.2 mm step size, a 55-degree wall angle, and a 1000 mm/min feed rate on the inner and outer of the measured surface, the slightly different optimum values on the rotational speed are 1250 rpm and 1750 rpm for the inner and outer surfaces, respectively. On Analysis of Variance (ANOVA) showed the step size has a greater percentage contribution effect on the surface roughness of formed TWBs than any other parameter. Furthermore, confirmation test results using optimal conditions showed good agreement wit experimental findings.