航空複合材料層板嵌補式修補模擬分析之研究

Study on Simulation Analysis of Aerospace Composite Laminates by Scarf Repair

廖人安(Jen-An Liao)

指導教授 ： 洪健君

淡江大學/工學院/航空太空工程學系碩士班/碩士(2023年)

https://doi.org/10.6846/TKU.2023.00010

摘要

複合材料因為有著強度高重量輕之特性，已隨著製程技術的成熟而被大量使用；近年來不管是軍機、民航機機身甚至是風力發電機台葉片都能看到複合材料的身影，而複合材料修復也成為未來需要面對的問題。本研究以嵌補式修補工法應用於碳纖維層板修復作為研究方向，為了探討橢圓嵌補塊修復複合材料層板之可行性，本研究以嵌補比和橢圓偏心率為修補塊設計考量；使用有限元素分析軟體輔助嵌補塊尺寸設計，並透過三點彎曲試驗的最大變形量作為比較層板在修補前後的強度標準。
本研究使用有限元素分析軟體分析T300/LTM45-EL複合材料，採用疊層方向為[0/90/45/-45]s試片並以不同修補塊接合介面進行應力分析，進一步發現當嵌補比為30之試片具有最小的變形量。本研究以嵌補比30作為橢圓嵌補塊尺寸設計，再進一步探討不同橢圓偏心率對修復層板抗彎曲負載程度的影響。
本研究建議未來能夠透過超音波檢測法確保實驗試片的品質，避免因為試片瑕疵影響實驗結果。若要將實驗與模擬相互比較，應該確保模擬模型的設計尺寸是否符合實驗設備適用範圍；加以膠合行為對於複合材料修復研究亦極為重要，也是未來值得研究的方向。此外複合材料層板之橢圓孔洞分析亦有助於橢圓嵌補塊設計相關研究。

關鍵字

嵌補式修補 ； 碳纖維層板 ； 複合材料修復 ； 有限元素分析 ； 三點彎曲試驗

並列摘要

Because of its high strength and light weight, composite materials have been widely used with the maturity of manufacturing technology. In recent years, composite materials can be seen in military aircraft, civil aircraft fuselages and even wind turbine blades. The composite repair has also become a problem that needs to be faced in the future. In this study, the application of scarf repair method to the repair of carbon fiber laminates will be considered in this research. In order to explore the feasibility of repairing composite laminates with ellipse repair patch, this research considers the scarf ratio and ellipse eccentricity to design the repair patch. The finite element analysis software is used to assist in the size design of repair patch, and the maximum deformation of laminates through the three-point bending test is used for comparing the strength before and after repair.
In this research, finite element analysis software is used to analyze T300/LTM45-EL composite materials, the specimen with the stacking sequences [0/90/45/-45]s was subjected to stress analysis under different repair patch sizes, and it is found that the specimen has the smallest deformation when the scarf ratio is 30. And the scarf ratio 30 considered to used as the size design of the ellipse repair patch, and the influence of different ellipse eccentricities on the bending load of repaired laminates is also discussed.
Finally, this study suggests that the quality of the experimental specimen could be ensured through ultrasonic testing (UT) to avoid the influence of experimental results due to specimen defects. To compare experiments with simulations, it should be ensured that the design dimensions of simulation model fit within the repairable range of experimental equipment. Cohesive behavior is important for the repair of composite materials, and it is also worth to study. Furthermore, the analyses of elliptical holes in composite laminates is helpful for the design of elliptical patches.

並列關鍵字

Scarf Repair ； Carbon Fiber Laminates ； Composite Repair ； Finite Element Analysis ； Three-Point Bending Test

參考文獻

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