埋入射出成型之模流及翹曲變形分析之研究

Abstract

近年手機相關產業在全世界迅速發展，令人驚艷的產品不斷被推陳出新，尤其是現今最熱門的『智慧型手機』，更是帶給消費者更多輕巧性、多功能性、可提昇工作效率的產品體驗。手機除了設計多樣化，亦提昇產品的功能，朝向輕、薄、短、小來發展已成為一個趨勢。 為因應此一趨勢，產品外觀零件的厚度必需力求減少；塑膠件之厚度由過去的 2~3mm，隨著產品設計理念的演變，已降至1.0mm以下。然而，塑膠零件厚度越薄，越不利於結構強度。因此，有關埋入射出成型的生產技術益形重要。 本研究利用Moldex3D軟體進行智慧型手機後殼模流分析，以模擬及數值解析方式，配合田口實驗設計法去尋求射出成型製程條件的優化。對於成型製造過程中的充填、保壓、塑膠材料、熔膠溫度、充填時間、充填壓力等影響，利用模流分析的方法多維考慮，在品質獲得保證的情況下，以產品零件翹曲、變形尺寸最小等，為評估選擇的指標。研究結果顯示，運用田口直交表可有效降低數值實驗組次數，並經由變異數分析找出影響品質變異的因子，以及各因子影響顯著的程度，其中充填時間與保壓時間為影響產品翹曲變形最具影響力的製程參數。 透過本研究結果，得到手機後殼成型最佳化的參數，可作為未來埋入射出件射出成型的參考，滿足目前日新月異的工業界對產品的品質、速度、精確性的要求。

In recent years, the mobile phone industry has undergone rapid global development, and eye-catching products continue to emerge, especially today’s most popular smartphones that bring consumers the product experience of lightweight, versatility, and improved work efficiency. In addition to the phone design diversity, the functionality of products has also been enhanced. The development toward light, slender, short, and small phones has become a trend. In response to this trend, the thickness of external product components must be minimized. With the evolution of the product design concept, the thickness of plastic pieces has been reduced from 2-3mm in the past to under 1.0mm. However, the thinner the thickness of a plastic piece, the less conducive it is to the structural strength. Hence, the insert-molding production technology has become increasingly important. In this study, the Moldex3D software was adopted for the analysis of the mold flow of smartphone rear casings. Through simulation and numerical analysis, coupled with the Taguchi experimental design method, the optimization of the injection molding process conditions was sought. As for the effects of filling, packing, plastic materials, melt temperatures, filling time, and filling pressure, the mold flow analysis method was adopted for multidimensional considerations. With the guaranteed quality, the warping of product parts and the smallest deflection size served as indicators for assessment and selection. The results show that the use of Taguchi can effectively reduce the number of numerical experiment groups. Additionally, through the analysis of variance, the factors affecting variations in the quality and the impact level of the factors were found. In particular, the filling time and dwell time were the most influential process parameters affecting product warpage deflection. Based on the findings of this study, the optimized parameters for the molding of mobile phone rear casings were obtained, which shall serve as a reference for the injection molding of insert-molding pieces in the future, thereby meeting the ever-changing industrial sector’s need for quality, speed, and accuracy.