Abstract:A kind of dynamic mold temperature control and cavity gas counter pressure assisted microcellular injection molding technique was established. The corresponding dynamic mold temperature control system and cavity gas counter pressure control system were developed, the dynamic mold temperature control and cavity gas counter pressure assisted microcellular injection molding test line were constructed, and the evolution of inner and outer cell structure of the molded parts were studied. The results show that when the dynamic mold temperature control or cavity gas counter pressure is applied to microcellular injection molding separately, it has double effects on the inner and outer cell structure of the molded parts: the dynamic mold temperature control can improve the most surface appearance of the molded parts, but has little effect on the melt foaming during filling stage; the cavity gas counter pressure can basically inhibit the melt foaming during filling stage, but has a significant effect on reducing the cell density of molded parts. Through coordinated controlling of dynamic mold temperature and cavity gas counter pressure, the inner and outer cell structure of the microcellular injection molded parts can be well regulated.