近年來，節能已成為大多數國家的主要關注點。汽車生產行業目前的重點是如何減輕車身重量並提高汽油使用的經濟性。部分汽車零部件已採用玻璃纖維或碳纖維增強塑料複合材料替代鋼材，以達到輕量化和高燃油效率的目標。聚合物產品最普遍的製造工藝是注塑成型。注塑成型在產品的大規模生產中提供了許多優勢，包括產品週期短和成品維護成本低，這兩者都有助於製造業務。本研究的重點是在螺旋流動模具上註塑成型後的纖維行為，特別是其纖維取向行為。將通過改變關鍵實驗設置、螺桿速度和背壓以及採用不同的熔體路徑來檢查玻璃纖維的行為。結果表明，高背壓和高螺桿轉速的應用分別使纖維長度減少了 25% 和 10%，但成功地增加了在流動方向的平均纖維取向。這裡採用的熔體流動路徑設計顯示出不平衡的模具填充現象，導致不對稱的纖維取向層次。同時，結合實驗參數的正確設置和熔體流動路徑的正確選擇，能夠產生非常高的張量值，超過 80% 的纖維在流動方向上對齊。

In recent years, energy conservation has been a major concern in most countries.
The present focus in the automotive production industries, is on how to lower the weight of the vehicle body and enhance the economy of gasoline usage. Glass fiber or carbon fiber reinforced plastic composite materials have been used for some automobile parts to replace steel materials in order to reach the goal of lightweight and high fuel efficiency. The most prevalent fabrication process for polymer product is injection molding. Injection molding provides numbers of advantages in the mass production of items, including a short product cycle and low maintenance of the finished product, both of which are helpful to the manufacturing business. This research focus es on the fiber behavior following injection molding on a spiral flow mold, particularly its fiber orientation behavior. The behavior of the glass fiber will be examined by altering key experiment settings, the screw speed and the back pressure and employing different melt paths. The results show that the application of high back pressure and high screw speed decreased the fiber length up to 25% and 10%, respectively, but successfully increased the fiber orientation average to the flow direction. The design of the melt flow paths that employed here are showing imbalance mold filling phenomena that resulting asymmetric fiber orientation hierarchy. Meanwhile, with the combination of correct settings in the experimental parameters and the right choice of melt flow path are able to create a very high tensor value with more than 80% fibers aligned in the flow direction.

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