Fatigue Damage Evaluation of GFRP Using Infrared Thermography -Effects of Matrix Resin and Fiber Content on Evaluation of Fatigue Damage-
Ken KURASHIKI, Qing-Qing NI and Masaharu IWAMOTO
Abstract:It may be difficult to make quantitative damage evaluation for FRP composites by means of traditional methods due to the occurrence of various damages and their interactions. On the other hand, for GFRPs under cyclic loading, the temperature rise was observed and there existed a good relationship between fatigue damage and temperature rise. Particularly it was possible to quantitatively evaluate the fatigue damage at the middle term of lifetime for GFRPs. However, there are a lot of factors that may affect the temperature rise in GFRP composites, and the property of matrix and fiber content are two main parameters. Thus, in this paper, the fatigue temperature rise curve for GFRP composites of continuous glass fiber reinforced CP-resin was obtained. Two kinds of matrix resin, one has much better elongation property than the another, were used and several fiber contents were prepared for the specimens. Then the effects of both matrix resin and fiber content on fatigue temperature rise curve were examined. As a result, it was found that the fiber content had much larger influence than the property of matrix resin on fatigue temperature rise. It was also found that the proposed evaluation method would be especially effective for the GFRP composites with high fiber content and brittle matrix. Key Words:GFRP, Fatigue, Fatigue damage, Infrared thermography, Fatigue thermal curve, Thermal conductivity