碳纖維/環氧樹脂複材板疲勞損傷及勁度衰減之關係研究

結構歷經長時間的外力作用後會有疲勞、裂縫或損壞的現象，因此檢測內部的損傷是一門重要的課題，而藉由非破壞檢測技術來檢測堪用結構材料內部的缺陷、裂縫是一個不錯的方法。本研究建立[0o]8疊層碳纖維複合材料在不同的特定應力參數條件時的疲勞損傷的檢測方法，並以疲勞勁度衰減觀點建立疲勞損傷與其壽命之關係模型。本研究以所設定的特定應力頻率、應力比及應力強度為參數，將歷經某特定應力週數試驗後之試片以C-SCAN做檢測，並取得其平面損傷掃描影像；再配合所撰寫的軟體程式作數位影像之轉換，藉以量化此複材試片的疲勞損傷程度值。再根據實驗時所測得的疲勞勁度與此量化的疲勞損傷值比對、建立疲勞損傷/勁度之關係模型。最後，並以實驗檢測此方法的準確性，並作該複材受疲勞應力時之殘留壽命的評估。

關鍵字

疲勞；碳纖維疊層板；破壞； C-Scan ；勁度

並列摘要

Materials of a structure under successively cyclic loading for a period will present the phenomenon which is crack, fatigue or structure breakage. The non-destructive evaluation method is a good choice which can avoid further destroying the structure to realize the damage level of the structure.This study established a technology which combined ultrasonic inspection procedures with digital image correlation method to analyze and to quantify the damage level and then investigated the degradation of fatigue stiffness of single-directional-fiber composites. It explored the fatigue damage properties of carbon/epoxy laminate by conducting the fatigue testing in the room temperature under specific stresses, frequencies, and stress ratios. Inspection images of the loaded specimens by C-Scan were obtained and the quantifications of the fatigue damage levels by self-developed digital image correlation code were done. The obtained results were used to analyze the quantitative fatigue damages and develop a fatigue stiffness degradation model. Finally a series of fatigue tests had been conducted to look over the proposed fatigue damage model.

並列關鍵字

Fatigue ； Carbon/Epoxy Laminate ； Damage ； C-Scan ； Stiffness

參考文獻

[2] Maria Kashtalyan, Costas Soutis, 2007,” Stiﬀness and fracture analysis of laminated composites with oﬀ-axis ply matrix cracking”, Composites: Part A, 38,pp.1262-1269

[3] Satoshi Kobayashi, Kazuhiro Terada, Shinji Ogihara, Nobuo Takeda,2001,” Damage-mechanics analysis of matrix cracking in ross-ply CFRP laminates under thermal fatigue” Composites Science and Technology ,61,pp1735-1742,

[4] Akira Todoroki , Kazuomi Omagari, Yoshinobu Shimamura, Hideo Kobayashi, 2006,” Matrix crack detection of CFRP using electrical resistance change with integrated surface probes”, Composites Science and Technology, 66,pp.1539-1545,

[5] Ercan Sevkat, Jackie Li, Benjamin Liaw, Feridun Delale, 2008,” A statistical model of electrical resistance of carbon ﬁber reinforced composites under tensile loading”, Composites Science and Technology ,68,pp.2214-2219,

[6] P. Berbinau, C. Soutis, I.A. Guz, 1999,” Compressive failure of [0] unidirectional carbon-fibre-reinforced plastic (CFRP) laminates by fibre microbuckling”, Composites Science and Technology, 59,pp.1451-1455,

國際替代計量

碳纖維/環氧樹脂複材板疲勞損傷及勁度衰減之關係研究

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