To produce thin-walled molds well, the fluidity of thin-walled injection molding materials must be good, and must have a large flow-to-length ratio. It also has high impact strength, high heat distortion temperature, and good dimensional stability. In addition, the heat resistance, flame retardancy, mechanical assembly and appearance quality of the material should also be investigated. Let’s take a look at the theoretical basis of thin-walled mold forming.
At present, materials widely used in injection molding include polypropylene PP, polyethylene PE, polycarbonate (PC), acrylonitrile-butadiene-styrene (ABS) and PC/ABS blends. The filling process and cooling process of conventional injection molding in the mold are intertwined. When the polymer melt flows, the melt front meets the core surface or cavity wall with a relatively low temperature, and a layer will be formed on the surface The condensation layer, the melt continues to flow forward in the condensation layer, and the thickness of the condensation layer has a significant impact on the flow of the polymer.
A more in-depth and comprehensive study is needed on the nature of the condensation layer in thin-wall injection molding. Therefore, a lot of work needs to be done on the numerical simulation of thin-walled injection molding. The first point is to conduct a more in-depth and comprehensive study of the theory of thin-wall injection molding, especially the properties of the condensation layer, in order to propose more reasonable assumptions and boundary conditions. From the above analysis, it can be seen that in the process of thin-wall injection molding, many conditions are very different from those of conventional injection molding.
When simulating, many assumptions and boundary conditions of the melt flow mathematical model need to be properly adjusted in thin-wall injection molding.
Post time: Dec-17-2022
