射出成型特徵結構於含玻纖之LCP材料纖維排向影響探討

Effects of Different feature structures on Fiber Orientation Distribution of Liquid Crystal Polymer (LCP) Material in Injection Molding

盧冠男(Guan-Nan Lu)

指導教授 ： 楊申語

國立臺灣大學/工學院/機械工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.10759

摘要

本研究探討LCP E130i於四種基本幾何形狀之現象，此四種基本幾何形狀為平板、圓弧、方波以及城垛型結構。主要射出參數為模溫以及射速，在模溫117℃以及模溫差90℃(母模117℃以及公模27℃)之下變化四種射速(45mm/s、90mm/s、135mm/s以及180mm/s)，探討纖維排向於翹曲之影響；在此模擬分析輔助觀察實驗結果。
在平板實驗中，當模溫為117℃時纖維排向對稱，翹曲量頗小；在模溫差90℃下，纖維排向不對稱性導致翹曲上升，結果指出纖維排向不對稱性以及中心層比例會影響到零件翹曲；圓弧以及方波纖維排向由於轉角效應，其排向不對稱性比平板大；在模溫差90℃下，翹曲量上升；針對城垛型結構實驗，在模溫117℃之下，由於零件厚度變化，纖維排向呈現更加不對稱；在模溫差90℃下，零件翹曲量下降。
其結果指出對於厚度變化之零件(例如城垛型結構)，模溫差可減少翹曲；本研究之成果可以應用改善分析之準確性。

關鍵字

纖維排向 ； 液晶高分子 ； 射出成型

並列摘要

This study is devoted to investigating the effects of the four basic geometries on the fiber orientation of LCP E130i. The four basic geometries are the flat plate, the arc, the square wave and the battlement respectively. The major injection parameters are mold temperature and injection speed. To discuss the effects of fiber orientation on the warpage, we set two experimental temperature conditions: (1) the injection conditions of 117℃ mold temperature, and (2) 90℃ mold temperature difference between the male mold temperature of 27℃ and the female mold temperature of 117℃. Both of the conditions are operated at four various injection velocities (45mm/s, 90 mm/s, 135mm/s and 180 mm/s) in this experiment. The simulation analysis is also to assist the observation of experimental results.
In the experiment of the flat plate, as the mold temperature is 117℃, the fiber orientations are symmetric, and the warpage of the parts are very small in various injection velocities. Under the temperature difference of 90℃, the non-symmetry of the fiber orientation leads to greater warpage. The results prove that the non-symmetry of the fiber orientation and the rate of core layer and part thickness have obvious influence on the warpage.
The experimental results show that the distributions of fiber orientation in the arc and the square wave are more non-symmetric than that in the flat plate because of corner effect, and hence a greater warpage, especially in a molding parameter of the temperature difference of 90℃.
For the experiment of battlements, the fiber orientations are more non-symmetric because the part has the thickness variance as the mold temperature is 117℃. The warpage of the part decreases in the temperature difference of 90℃.
In conclusion, the results prove that adjusting the temperature difference can decrease the warpage when the part has the thickness variance such as the battlements shape. The results can be applied to improve the accuracy of simulation.

並列關鍵字

Fiber orientation ； LCP ； Injection molding

參考文獻

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