Accelerated testing for long-term durability of FRP laminates for marine use

The accelerated testing methodology has been proposed for the long-term durability of polymer composites based on the time-temperature superposition principle to be held for the viscoelasticity of polymer matrix. In this paper, the longterm flexural fatigue life of plain woven carbon fiber-vinylester (CFRP) laminates for advanced marine use was predicted based on the proposed methodology, compared with that of plain woven glass fiber-vinylester (GFRP) laminates for conventional marine use. The applicability of the accelerated testing methodology for these laminates and the advantages of this CFRP laminates are discussed. As results, the flexural fatigue strength of CFRP laminates as well as that of GFRP laminates clearly depends on time and temperature. The time-temperature superposition principle for the viscoelasticity of matrix vinylester resin holds for these flexural fatigue strengths, and then the master curves can be obtained. It is clear from these master curves that while the flexural fatigue strength for GFRP laminates decreases strongly with increasing number of cycles to failure N-f and that for CFRP laminates decreases scarcely with increasing N-f.