Parameter Optimization of Injection Molding Ti-6Al-4V Powder and Palm Stearin Binder System for Highest Green Density Using Taguchi Method

In this paper, the titanium alloy powder of Ti-6Al-4V is mixed with binder 60wt% of palm stearin and 40wt% of polyethylene for metal injection molding (MIM) process. Injection molding parameters has been optimized using Taguchi method of L27 (313) orthogonal array. Highest green density has been identified as the green part quality characteristic or as an output for this study. Parameters optimized are the injection pressure, injection temperature, powder loading, mold temperature, holding pressure and injection speed. Besides those, interaction of the injection pressure, injection temperature and powder loading were studied. The analysis of variance (ANOVA) is employed to determine the significant levels (α) and contributions of the variables to the green density. Results show that the injection pressure has highest significant percentage followed by injection temperature, powder loading and holding pressure.