鋁合金模仁應用於改善少量多樣射出產品翹曲變形之探討

Study on the Warpage Improvement in Small Amount of Diversity Injection Molded Parts with Aluminum Mold Insert

王國瑞(Kuo-Jui Wang)

指導教授 ： 陳夏宗

中原大學/工學院/機械工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000617

摘要

中文摘要
在射出成型過程中，塑膠製品在模腔中的冷卻時間要占整個成型週期很大的比重約60%~70%，所以射出成型模具冷卻系統設計的良窳是模具設計成功與否的一個關鍵因素，而冷卻的速度和均勻性會直接影響到塑膠製品的生產效能和品質。然而在實際模具設計過程中往往因為塑膠製品的幾何形狀、結構設計、模具頂出機構、模具結構…等因素，而影響模具公、母模仁冷卻水路的配置和數量的多寡，使得模具溫度分佈不均，模溫差造成塑膠製品產生翹曲變形問題。
本研究的目的在探討當公模仁水路配置自由度低於母模仁水路配置的情況下，利用熱傳導性較佳的QC-10鋁合金材料，將公模仁積熱快速帶離；使公、母模仁溫度場分佈更趨均勻且使公、母模仁溫度差減小從而改善塑膠製品的翹曲變形量。
研究中首先利用CAE軟體進行全因子組別的模擬，以獲得在改變各單獨製程參數模具溫度、熔膠溫度、保壓時間、冷卻時間的情況下對兩種材質模仁成型的產品翹曲變形的影響。從分析結果顯示QC-10對翹曲變形改善率平均達58.27%的效益。而實際成品量測結果其平均改善翹曲變形量效益達32.01%。從溫度場的分析與實驗驗證兩種材質模仁熱傳導的優劣性，經由CAE軟體分析和實驗量測結果相互印證顯示，QC-10的熱傳導性能有效的消除模具局部熱點降低模溫差5-10°C對改善翹曲變形具有彰顯的效益。
關鍵詞: 均勻溫度、鋁合金、冷卻速率、翹曲變形

關鍵字

均勻溫度 ； 鋁合金 ； 冷卻速率 ； 翹曲變形

並列摘要

Abstract

The temperature uniformity of a cavity/core and the cooling system design has become the key issue of a part quality. Besides, the cooling speed and the cooling uniformity will affect the part quality and molding efficiency. But the ideal cooling system design may not able to realize due to part geometry, core and cavity structure and ejection system.
In this study, the QC-10 aluminum material with high heat transfer performance had been made into the cavity/core insert for increasing the temperature uniformity of cavity/core and decreasing the temperature difference between cavity and core and reducing the part warpage. The CAE tool had been applied to verify the effect of temperature uniformity and part warpage of QC-10 aluminum core insert. The processing conditions study include mold temperature, melt temperature, packing time and cooling time. It was found that the improvement of part warpage can have 58.27% in simulation and 32.01% in experiment. The QC-10 aluminum can transfer the heat faster than the NAK-80 mold steel result in decreasing the temperature difference between cavity and core from 5℃ to 10℃.
From this study, both simulation and experiment had shown the high heat transfer aluminum core can improve the temperature uniformity of a mold and reduce the part warpage. Hope this study can provide an effective design method for mold maker to solve the warpage problem.
Keywords：Temperature uniformity, aluminum, cooling speed, warpage.

並列關鍵字

warpage. ； cooling speed ； aluminum ； Temperature uniformity

參考文獻

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