Abstract: The influence of different processing parameters on the average birefringence was simulated using Moldflow software. The optimized parameter of each factor′s contribution to the average birefringence was studied with orthogonal experimental method, and then the single factor experimental method was utilized to study the effect of different processing parameters on the average birefringence of the part. It showed that holding time and melt temperature contributed the most to the average birefringence, but the influence mechanism of them to the average birefringence was different. The holding time had a significant effect on birefringence only near the gate, while the melt temperature had an effect on birefringence in the whole area.

Key words: injection molding, birefringence, threedimensional simulation, orthogonal experiment