AEの周波数解析によるFRPETの破壊機構に関する研究

センサーの位置と引張速度の影響

抄録

In order to classify the fracture mechanism of composite materials, the PET resin and the model FRP test specimens were prepared and the relation between the detected AE frequency and the damage mode of those test specimens was examined by performing tensile tests. The effects of sensor position and tensile speed on the frequency characteristics were also examined by using FRPET test specimens. The results obtained are as follows:
(1) The AE frequency ranges corresponding to the resin cracking in the PET test specimen, the fiber debonding and pulling out and the fiber breakage in the model test specimens were 60-240, 240-330 and 350-420kHz, respectively.
(2) When the distance between the sensor and the center line of FRPET test specimen was changed from 20mm to 30mm, the AE signal also changed due to the wave attenuation; the peak frequencies which correspond to the fiber breakage and the fiber debonding and pulling out shifted to the higher frequency side, and the power spectrum at the frequency which corresponds to the resin cracking became lower.
(3) When the tensile speed of FRPET test specimen was changed from 0.2mm/min to 0.05mm/min, the peak frequencies which correspond to the fiber breakage and the fiber debonding and pulling out shifted to the lower frequency side and the power spectrum became lower. The power spectrum at the frequency which corresponds to the resin cracking was affected by the tensile speed and became higher.