超音波疲労試験技術による炭素繊維強化プラスチック擬似等方性積層板の超高サイクル疲労特性の評価

抄録

Carbon fiber reinforce plastics have been applied to structural materials of blades of wind turbines and aircraft turbine engines. These blades may suffer from very high cycle fatigue up to 108–1010 cycles. However, conventional fatigue testing methods consume longer period in excess of 1 year for obtaining only 1 fatigue data in the very high cycle region. Recently, several researchers have reported that an ultrasonic fatigue testing method enables us to conduct accelerated bending and axial fatigue testing. In this study, an ultrasonic fatigue testing method was applied to accelerate axial fatigue testing of CFRP laminates in the very high cycle regime. In order to discuss the feasibility, a specimen shape for ultrasonic fatigue testing was designed to achieve resonance at 20kHz. Then, fatigue testing was conducted up to 109 cycles, and the S-N property was compared with fatigue testing results by using a conventional serve-hydraulic fatigue testing machine.