- 學位論文
聚碳酸酯板材熱壓成型研究
Investigation of Polycarbonate Sheet Thermoforming Process
摘要
一般而言，厚度均勻的聚碳酸酯產品的製造多採用高效率、相對低成本的熱壓成形製程，然而，此製程迄今仍仰賴傳統的試誤法，不僅耗時成效亦有限，是故熱壓成形製品的品質一直難以提升。相較於其它熱塑性塑膠，聚碳酸酯於熱壓成形製程中展現出極高的韌性，其加工溫度亦相對較高，此外，更易發生成形失敗、缺陷或成品品質不佳等問題。 為了有效改善聚碳酸酯熱壓成形技術，本研究嘗試利用單軸拉伸試驗與迴歸分析，探討聚碳酸酯於高溫下的力學特性，同時，結合軸對稱真空成形實驗以及有限元素模擬結果，建立一個包含熱傳與溫度效應的聚碳酸酯力學模型並完成實驗驗證，之後，將此模型應用於評估聚碳酸酯熱壓成形結果，確立聚碳酸酯的成形極限，進而提出最合適的加工參數，以期改善聚碳酸酯熱壓成形製品的品質。最後應用於新能源車輛的零組件製作。
並列摘要
Although thermoforming has been used for many years, it still relies mostly on trial-and-error methods. The thermoforming of polycarbonate, results in defects or failure due to forming more frequently than other thermoplastics. The reason for this is the high toughness of polycarbonate and the relatively high operating temperature required to process it. Improving the techniques involved in controlling the manufacture parameters of these materials relies on an understanding of the fundamental behavior of polycarbonates at elevated temperatures. The aim of this study is improving the polycarbonate thermoforming techniques. The thermotensile experiments and regression analysis are conducted to characterize the mechanical behavior of polycarbonate under elevated temperature. According to the results of axisymmetric vacuum-forming experiments and numerical simulation, a comprehensive hyperelastic constitutive model of polycarbonate is constructed and applied in forming prediction. The ideal manufacture parameters are also provided through the above results. At the end of study, the polycarbonate thermoforming technique are applied in manufacturing the canopy and lampshades of hybrid motorcycle.