Relevance of mold‐induced thermal boundary conditions and cavity deformation in the simulation of injection molding

In this work an amorphous PS was injection molded into a simple line‐gated rectangular cavity. The effect on post‐filling pressure curves and temperatures (at the polymer‐mold interface) of different holding pressures and times, and of two gate thickness configurations, was analyzed. Molding tests were simulated leading to a good description of pressure evolution in different positions along the flow path for all molding conditions analyzed. Comparison between simulation results and experimental data shows that: considering a rigid mold can lead to predicted values of post‐filling pressure profiles much different from experimental ones; heat transfer coefficient description plays a minor role in the prediction of pressure evolution, but its effect is relevant on temperature evolution in layers dose to the mold surface.