Abstract: the influence of processing parameters(delay time, gas pressure, melt temperature, short-shot size) of gas-assisted injection molding on the gas penetration behavior (residual wall thickness, penetration length) was studied. It showed that the shorter delay time and higher melt temperature, the smaller the residual wall thickness. In addition, shorter delay time, lower melt temperature, and larger short-shot size may result in larger penetration length. By comparison, the residual wall thickness ratio obtained from this experiment was consistent with that from a previous simulation.

Key words: gas-assisted injection molding, gas penetration, delay time, short-shot size, polypropylene