Effects of forming parameters on metal flow behaviour during the MDF process: taguchi and response surface methodology optimisation

In this study, multidirectional forging (MDF) process parameters were optimised using Taguchi analysis and response surface methodology (RSM) for damage and effective strain. The parameters considered in the study were: temperature, friction coefficient, strain per pass, and die speed. Aluminium alloy 7075 (AA 7075) was used as a specimen for analysis during MDF processing. The output responses selected were maximum damage and effective strain. The MDF was undertaken at four levels for each input parameter. The Taguchi L₁₆ orthogonal array was used to determine the interaction of the inputs and the contribution of the parameters. Simulations of the process were carried out on Deform 3D software. The analysis of variance demonstrated that the contribution of strain per pass was the most significant in causing damage and an increment in effective strain. Temperature and die speed were shown to have minimal effects on the outputs. The confirmation simulations demonstrated that the optimal solutions obtained by the Taguchi method had damage of 1.29, and the effective strain was 2.88. The RSM results were 0.19984 and 4.02193 for damage and effective strain, respectively.