以光纖光柵與電壓監測碳纖維複材膠合接口受衝擊破壞之應用

Health monitoring impact damage on single lap CNT-epoxy joints of CFRP by using voltage change measurement and fiber Bragg grating sensors

簡慶丞(Ching-Cheng Chien)

指導教授 ： 單秋成

國立臺灣大學/工學院/機械工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202103033

摘要

本研究探討以光纖光柵與電壓監測碳纖維複材膠合接口受衝擊破壞之應用，利用環氧樹脂混入具導電性的奈米碳管作為搭接劑，將碳纖維強化複合材料(Carbon fiber reinforced plastics, CFRP)進行單搭接，並將布拉格光纖光柵感測器(fiber Bragg grating sensors, FBG)內埋至搭接面，觀察其頻譜變化，在電壓監測方面，將銅箔內埋至複合材料內並焊上電線來量測其整體電壓變化，最後利用螢光液滲法驗證其破壞。探討試片經衝擊破壞後，其頻譜與電壓的變化，嘗試建立一個判斷準則。在衝擊實驗結果中證實光纖光柵在搭接面中能有效感測衝擊所造成的破壞，且有局部偵測的效果，使用者能透過觀察其頻譜是否有出現劈裂與變寬的現象來判別此單搭接結構是否受到衝擊破壞，但使用者必須注意其偵測範圍，在頻譜觀察到劈裂與變寬現象時，並不表示衝擊破壞發生在光柵區域，然而破壞可能發生在鄰近光柵區域的某一特定距離內。電壓監測結果中證實電壓對衝擊破壞的監測也是相當靈敏，但無法做局部性監測，只能對整體搭接面做偵測，結合光纖光柵與電壓監測能有效監測在搭接面上的衝擊破壞。

關鍵字

單搭接膠合接口 ； 光纖光柵感測器 ； 碳纖維複合材料 ； 電壓監測結構完整性 ； 衝擊損傷監測

並列摘要

The purpose of this study is to use voltage change measurement and fiber Bragg grating (FBG) sensors to monitor impact damage on single lap CNT-epoxy joints of carbon fiber reinforced plastics (CFRP). The adhesive is made of epoxy resin mixed with carbon nanotubes, which is conductive. Use adhesive to make a single lap CNT-epoxy joints of CFRP. By embedding FBG in the adhesive joint, it can measure the frequency spectrum. Embedding copper foil in CFRP and welding the wire to measure the voltage change in the experiment. Final step is to use fluorescent penetrant testing method to show that there is indeed a damage position in the adhesive joint. This study try to create a criterion after analyzing the frequency spectrum and voltage change. The result of impact test confirms that FBG can effectively detect local damage in the adhesive joint. User can judge whether the single lap joint structure has experienced the impact damage by observing the change of frequency spectrum, but it has to be noticed that when FBG detect the damage, it does not show that the damage occur on position of FBG. However the damage may occur near the FBG within a specific distance. The result of voltage change measurement confirm that voltage is sensitive to the impact damage, but it can only monitor the damage of entire adhesive joint. Applying both of voltage change measurement and fiber Bragg grating sensors can effectively monitor impact damage on adhesive joint .

並列關鍵字

Single lap joint ； Optical fiber grating ； Carbon fiber reinforced plastic ； Voltage change measurement ； Health monitoring for impact damage

參考文獻

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