Improvement of ductility for squeeze cast 2017 A wrought aluminum alloy using the Taguchi method

Abstract

In this paper, the influence of process parameters on the ductility during squeeze casting of 2017 A wrought aluminum alloy is studied. The Taguchi method of design of experiments was employed to optimize the process parameters and to increase the elongation percent. A 3-factor, 3-level casting experiment is conducted by Taguchi L9 orthogonal array through the statistical design method. Then, the input parameters are considered here including squeeze pressure, melt temperature, and die preheating temperature with three levels. The optimum casting parameters to acquire higher ductility were predicted, and the individual importance of each parameter was evaluated by examining the signal-to-noise (S/N) ratio and analysis of variance (ANOVA) results. The optimum levels of the squeeze pressure, melt temperature, and die preheating temperature were found to be 90 MPa, 700, and 200 °C, respectively. The ANOVA results indicated that the squeeze pressure has the higher statistical effect on the elongation percent, followed by the melt temperature and die preheating temperature. Optical microscopy and scanning electron microscopy (SEM) analysis were used to discuss the effect of pressure levels on the microstructure and the fracture characterization of the investigated alloy.