Plastic mold factories increase the injection pressure or holding pressure, which will increase the orientation stress. The high mold temperature can ensure that the product cools slowly and play a de-orientation effect. Increasing the thickness of the product reduces the orientation stress, because the thick-walled product cools slowly, the viscosity increases slowly, and the stress relaxation process takes a long time, so the orientation stress is small.
Plastic mold factories have high melt temperature, high melt temperature, low viscosity, and reduced shear stress. On the other hand, high melt temperature will accelerate stress relaxation and enhance the ability to de-orientate. Without changing the pressure of the injection molding machine, the cavity pressure will increase, and the strong shearing action will cause the orientation stress to increase. Before the nozzle is closed, extending the holding time will cause the orientation stress to increase.
