不同截面型腔的溢流法流体辅助注塑工艺的实验分析

Experimental Study of the Penetration Interfaces in the Overflow Fluid-assisted Injection Molding Process of Cavities with Different Cross-section

基于自行构建的流体辅助注塑实验平台,对5种不同截面型腔管件的溢流法气体辅助注塑(GAIM)和水辅助注塑(WAIM)进行了实验研究。研究了辅助介质对管件流体穿透截面形状、残余壁厚大小和流体穿透率的影响规律以及工艺参数对流体穿透率的影响规律,并分析了其影响机理。实验发现:气体的穿透截面趋于型腔截面形状,水的穿透截面趋于圆形;GAIM的五截面管件的最小残余壁厚均大于WAIM,最大残余壁厚均随着内切圆圆心到壁面的最大距离的减小而减小;气体的穿透率较水的穿透率小,均随着圆率的增加而增加,随气体/水注射压力的增加而增加,随气体/水注射延迟时间的增加而减小,随熔体注射温度的增加而有所增加。这些发现为GAIM和WAIM制品截面设计及工艺参数调节提供了参考。

The experimental study of gas assisted injection molding （GAIM） and water assisted injection molding （WAIM） of five fittings with different cross-section cavities were carried out based on a labdeveloped fluid-assisted injection molding （FAIM） system. The affection laws of assisted mediums on the shape of penetration cross-section of the fluid, the maximum distance between the inscribed circle center and the wall, and the penetration ratio of fluid were studied, and the mechanism was also analyzed. The experiment results show that the cross-section shape of gas penetration tends to be the shape of the cavity cross- section while the cross-section shape of water penetration tends to be round. The gas penetration ratio is less than the water penetration ratio. The gas/water penetration ratios increase with increasing the circle ratio or the injection pressure of gas/water or the melt temperature, and they decrease with increasing the gas/water injection delay time. These results provide a reference for the design and the adjustment of process parameters of GAIM and WAIM products section.