大曲率明膠玻璃拉伸成形製程研析

Abstract

飛機之風擋及座艙罩等明膠玻璃產品，傳統上多依賴人工操作或低階自動化方式進行生產，隨著產品外型日益複雜且不等曲率之設計需求提升，傳統生產方法難以滿足高精度與穩定性之需求。為了提升生產效率和產品品質，本研究旨在建立一套自動化拉伸成形系統，結合電動及油壓伺服拉伸缸進行明膠玻璃產品拉伸成形，並藉由電腦輔助工程(Computer Aided Engineering, CAE)模擬技術，建立完整製程分析之模擬模型，以優化自動化拉伸成形製程。 為建立完善拉伸成形模擬模型，首先需詳細探討明膠玻璃之材料特性，本研究進行了明膠玻璃之高溫拉伸實驗、熱膨脹實驗以及透過熱機械分析儀進行其餘相關熱性質實驗，並且透過上述實驗所得之參數，建構與溫度具有高依賴關係之材料模型。透過參考文獻並選用彈塑性材料模型，於有限元素分析軟體Abaqus中選用隱式(Implicit)靜態分析步驟(Statics, General)模擬變形行為，並驗證材料模型準確性。 本論文首先以縮小比例模型建立基礎拉伸成形技術，並參考實際載具建立CAE模擬模型，探討拉伸缸設備之作動方式及其對於明膠玻璃拉伸成形中潛在缺陷之影響，接著透過實際實驗驗證拉伸設備作動之可行性，為自動化拉伸成形技術建立基礎。 完成基礎拉伸設備之設計與作動驗證後，本研究進一步針對明膠玻璃實際座艙罩產品之拉伸成形進行其設備與模擬模型之建立。根據座艙罩模具之幾何特徵，結合拉伸設備不同作動型態，建立完整CAE模擬模型。模擬中針對不同下料尺寸與製程參數對成形過程中潛在缺陷進行探討，並針對不同製程產生之缺陷進行分析及改善，作為後續其他製程參數優化與產品品質提升之依據，進一步建立完整明膠玻璃拉伸成形技術。 本研究亦針對尺寸精度及其光學品質進行探討，結合模擬結果與光學理論，分析影像扭曲、偏折等問題，建立製程參數與成品品質之對應關係。此結果不僅有助於明膠玻璃成形製程之優化設計，亦可作為未來自動化生產系統之理論依據及實務參考。

Traditional production methods for aircraft transparency components, such as windshields and canopies made of acrylic glass, predominantly rely on manual operations or low-level automation. As product geometries become increasingly complex with demanding linear curvature requirements, conventional manufacturing approaches struggle to meet precision and stability requirements. To enhance production efficiency and product quality, this study establishes an automated stretch-forming system incorporating electro-hydraulic servo-controlled stretch cylinders for acrylic glass forming. Computer-Aided Engineering (CAE) simulation technology is employed to develop a comprehensive process analysis model for optimizing automated stretch-forming parameters. To construct an accurate stretch-forming simulation model, this research first investigates the material properties of acrylic glass through high-temperature tensile testing, thermal expansion analysis, and thermomechanical characterization using a Dynamic Mechanical Analyzer (DMA). The experimental data is used to develop a temperature-dependent material model. Based on literature review, an elastoplastic material model is selected and implemented in Abaqus finite element analysis (FEA) software, where implicit static analysis (Static, General) simulates deformation behavior, with subsequent validation of the material model's accuracy. This study initially develops fundamental stretch-forming techniques using scaled-down prototypes, establishing CAE simulation models based on actual aircraft transparency geometries. The actuation mechanisms of stretch cylinders and their influence on potential forming defects are systematically analyzed. Experimental validation confirms the feasibility of the stretch-forming apparatus, laying the groundwork for automated forming technology. Following the preliminary validation, the research advances to full-scale canopy stretch-forming by developing corresponding equipment and simulation models. The CAE model integrates the geometric characteristics of canopy molds with diverse cylinder actuation modes to predict forming defects. Parametric studies on blank dimensions and process variables identify defect formation mechanisms, enabling process optimization for enhanced product quality. The study further investigates dimensional accuracy and optical performance by correlating simulation results with optical theory to analyze image distortion and light deviation. The established process-quality relationships provide critical insights for optimizing acrylic glass forming processes and serve as a theoretical foundation for future automated production systems.