本文研究以玻璃纖維(Glass Fiber)強化聚甲醛(POM)之複合材料為對象，與探討在不同射出成型(Injection Molding)製程參數下，如熔融溫度、模具溫度、保壓壓力、射出速度與保壓時間對於機械性能之影響。藉由田口方法(Taguchi Method)中的直交表設計實驗，並以田口方法中的主效果分析與變異數分析理論得到單一品質的最佳化參數，並將實驗所得之各品質數據，經由主成份分析法(Principal Component Analysis)結合灰關聯分析法(Grey Relation Analysis)找出多品質最佳製程參數水準之組合。研究結果顯示，若同時考量拉伸強度、硬度、衝擊強度與彎曲強度四項多品質特性時，其最佳條件為玻璃纖維添加20 wt.%、熔融溫度230℃、模具溫度60 ℃、保壓壓力50 MPa、射出速度60 mm/s與保壓時間1.5 s，最後證實本研究所規劃之實驗能對材料之多品質有效的提升與有良好的再現性。

This study investigates the influence of injection molding process parameters on mechanical properties of glass fiber reinforced polyoxymethlene (POM/GF) composites. The process parameters include melt temperature, mold temperature, packing pressure, injection speed and packing time. The taguchi orthogonal array table is used to design the experiment. The factor effect analysis and analysis of variance are conducted on quality data in order to determine the optimal parameters for single quality. The quality data are processed by principal component analysis and grey relation analysis to determine the optimal parameters of four qualities. The four qualities considered in this study are the tensile strength, hardness, impact strength and bending strength. The resulting optimal injection molding process conditions are 20 wt.% glass fiber addition, melt temperature 230 ℃, mold temperature 60 ℃, packing pressure 50 MPa, injection speed 60 mm/s and packing time 1.5 secends. This study effectively enhances multiple qualities of the composite materials and has good reproducibility.

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