氣體反壓與動態模溫協同控制應用於超臨界微細發泡射出成型成型品品質改善之研究

Part Quality Improvements during Microcellular Injection Molding Process via a Control Mechanism of Gas Counter Pressure and Mold Temperature Variation

廖威量(Wei-Lianq Liaw) ； 林明俊(Ming-Chung Lin) ； 簡仁德(Rean-Der Chien) ； 陳夏宗(Shia-Chung Chen)

《桃園創新學報》 32期 (2012/12) Pp. 57-72

https://doi.org/10.6989/JTI.201212.0057

摘要

在本研究中，我們發展出模內氣體反壓（GCP）與動態模溫協同控制系統，用以控制超臨界微細發泡射出成型製程中之發泡，並研究其對成型品表面以及發泡品質之影響。實驗結果顯示在GCP單獨控制下，當氣體反壓壓力超過100 bar時，其表面粗糙度可改善90%。而氣體反壓壓力增加時，會使凝固層厚度增加，重量減低率降低且平均氣泡尺寸可降低至約30 μm。增加持壓時間，則氣泡密度降低且氣泡尺寸變得更加一致。使用90～120 °C（接近Tg）之模溫區間單獨控制時，表面粗糙度則可增進65%。增加模具溫度將會降低凝固層厚度，然而氣泡尺寸大小分布卻變得嚴重不均勻。若是同時結合GCP與模溫控制時，則可同時達成凝固層厚度變薄、氣泡尺寸變小且具均勻性、以及得到較好之表面品質。

關鍵字

超臨界微細發泡射出成型 ； 氣體反壓 ； 模溫控制 ； 表面粗糙度 ； 氣泡尺寸

並列摘要

This study developed a foaming control using the Gas Counter Pressure (GCP) combined with mold temperature control during MuCell process and to investigate its relevant influence on parts' surface and foaming qualities. The results reveal that under GCP control alone when GCP is over 100 bar, part surface roughness can be improved by 90%. When GCP increases, the skin thickness also increases, the weight reduction decreases and the average cell size can be reduced to about 30μm. Increasing gas holding time the cell density is decreased and the cell size becomes more uniform. The increase in SCF level also increases the cell density. Applying mold temperature control alone with mold temperature range between 90~120 °C (near Tg), the surface roughness improved by 65%. Increasing mold temperature will decrease the skin thickness, however, the cell size becomes non-uniform distributed severely. Combined GCP and mold temperature control simultaneously, thin skin, small and uniform cell size as well as high surface quality can be achieved efficiently.

並列關鍵字

Microcellular Injection Molding ； Gas Counter Pressure ； Mold Temperature Control ； Surface Roughness ； Cell Size