Fatigue Damage Evaluation of Plain-Woven Carbon/Epoxy Composites by Using Thermo-Elastic Technique
Yasuhiro NISHIKAWA, Kazuya OKUBO, Toru FUJII and Toshiyuki UENOYA
Abstract:In this paper, damage progression process of plain-woven carbon/epoxy composites was investigated under cyclic loading. Damage state, damage degree and its location were observed in the flat-wise direction of the specimen by using thermo-elastic stress analysis (TSA). The results of TSA showed that transverse cracks initiated and accumulated in the wefts at early fatigue stage. The each location, where the damage occurred, had different damage degree at any fatigue cycles. In order to obtain accurate damage information, thermo-elastic damage analysis (TDA) was conducted. A quantitative evaluation of damage accumulation level in plain-woven carbon/epoxy composites was proposed based on the concept of damage parameters (such as damage level, damage area ratio and damage value) given by TDA results. Key Words:Fatigue damage, Quantitative evaluation, Plain-woven, Carbon/epoxy composite, Thermo-elastic stress analysis, Thermo-elastic damage analysis