在現今航太工業中，運用碳纖維複合材料(CFRP)的比例越來越高，但是其材料性質或是機械性質容易受到以下因素影響。例如:材料製造時產生的內部缺陷或是外來異物衝擊，這些因素皆會影響飛航安全。因此事先將缺陷區域檢測出來為重要的課題。但是檢測出缺陷區域以後，此為缺陷之二維資訊，仍無法檢測缺陷真正深度之所在，所以檢測缺陷深度成為另一個重要的資訊。
本研究之目的以結合反射式與穿透式梯波法(step heating)熱影像術為基礎，建立一套非破壞性缺陷深度檢測系統，檢測嵌有不同缺陷深度之碳纖維複合材料。將檢測之熱影像透過本文之缺陷深度檢測法計算含缺陷碳纖維複合材料之缺陷深度，並與試件實際製作情況作比對。此外，也利用ANSYS有限元素模擬分析軟體模擬缺陷及非缺陷區域之升溫、降溫變化與初始分離時間，並與實驗結果比對，結果顯示本文之缺陷深度檢測法可檢測出含缺陷碳纖維複材之缺陷深度，且具有一定準確性與可行性。

In recent years, the Carbon Fiber Reinforced Plastic(CFRP) was used to the aerospace industry. The material or mechanical properties can easily change due to the internal defect when the material made or external impact. It can result in the aeronautical safety. Therefore, detect the defect area in advance is the important issue. After the defect was detected, we just got the two-dimensional information of defect, it’s still enable to detect where the defect depth is. So, detecting the defect depth is the other of important information.
In this research, the purpose was based in linking both reflective and transmissive step heating and establish a non-destructive defect depth detection system so that detect different embedded defect depth of CFRP. To use the thermogram sequence to evaluate the embedded defect depth of CFRP by defect depth detecting method of this study, and compared with the actual condition of specimen. Moreover, it had been to use the finite element analysis (FEA) to simulate not only the heating and cooling of defect area and non-defect area, but also the early separate time, compared with the experimental results. Finally, the results show that this defect depth detecting method can detect different embedded defects depth values of CFRP, and has a certain accuracy and feasibility.

1. Carslaw, H. and Jaeger, J. “Conduction of heat in solids,” Oxford University Press, London, 1959.
2. D. Maillet, A. Houlbert, S. Didierjean, A. Lamine, and A. Degiovanni, “Non-destructive thermal evaluation of delamination in a laminate: Part I- Identification by measurement of thermal contrast,” Composites Science and Technology, vol.47, pp.137-153, 1993.
3. Adel A. Badghaish and David C. Fleming, “Quantitative characterization of resistive defect in thick composite using step heating thermography,” Proc. of SPIE, Vol.6939, pp.1-12, 2008.3
4. Liu Junyan, Wang Yang ,Liu Hui and He Yinhang, “Research on CFRP Materials Nondestructive testing by IR Lock-in Thermography”, Proc. of SPIE Vol. 7383, 73833U1-9,2009.
5. Jawdat Tashan, Riadh Al-mahaidi, “Investigation of the parameters that influence the accuracy of bond defect detection in CFRP bonded specimens using IR thermography, ” Composite Structures, 94, pp. 519–531, 2011.
6. 郭明軒, “將紅外線灰階熱影像轉換成溫度場進行材料內部缺陷檢測之研究” ,國立成功大學機械工程學系碩士論文, 2011。
7. 劉慶堂博士, “熱影像檢測技術應用於複合材料結構缺陷之探討” ,國立中興大學機械工程學系博士論文, 2012。
8. N. Rajic, “Principal component thermography for flaw contrast enhancement and flaw depth characterisation in composite structures,” Defence Science and Technology Organisation, Australia, 2002.
9. Akbar Darabi, Xavier Maldague, “Neural network based defect detection and depth estimation in TNDE,” Universite’ laval, Canada, 2002.
10. Huo-yan, Zhao Yue-jin, Zhang Cun-lin, Li Yan-hong, Zeng-zhi, “Depth measurement using infrared thermography, ” Proc. of SPIE, Vol. 7511, pp. 1-6, 2009.
11. Bradley G. Bainbridge, “Optimization of Transient Thermography Inspection of Carbon Fiber Reinforced Plastics,” Southern Illinois University, Carbondale, 2010.
12. B.B. Lahiri , S. Bagavathiappan , P.R. Reshmi , John Philip , T. Jayakumar a, B. Raj, “Quantification of defects in composites and rubber materials using active thermography, ” University of Kerala, India, 2012.
13. D. Sharath • M. Menaka • B. Venkatraman, “Defect Characterization Using Pulsed Thermography, ” J Nondestruct Eval, 2012.
14. Xavier P. V. Maldaque, “Theory and practice of infrared technology for non-destructive testing, ” Universit’e Laval, Canada, 2001.
15. 牛仰堯, 李先知, 姜巍棠 譯, “熱傳遞(上)”六合出版社,“ 2000。
16. P. Theodorakeas, N.P. Avdelidis, K. Hrissagis, C. Ibarra-Castanedo, M. Koui, X. Maldague, “Automated transient thermography for the inspection of CFRP structures: experimental results and developed procedures,” Proc. of SPIE , Vol. 8013, pp. 1-11, 2011.
17. 林冠宇, “複合材料缺陷之紅外線熱影像檢測及圖像分析” ,國立成功大學機械工程學系碩士論文, 2013。