繰返し負荷を受ける平織CFRPのピエゾ抵抗変化

抄録

The present study deals with electrical resistance change of woven-fabric CFRP during loading. Four kinds of plain weave woven-fabric CFRP laminated specimens are prepared. The specimens are subjected to cyclic tensile loading that does not cause any damages, and the electrical resistance changes of the specimens are experimentally measured by the four-probe method. As a result, the present study shows that the electrical resistance of a specimen comprising of six of ±45° plies remarkably decreases with the increase of the number of the loading cycle. The decrease is caused by the shear plastic deformation of ±45° plies. The thickness shrinkage caused by the shear plastic deformation increases the number of fiber contacts, and this decreases the interlaminar contact resistance between the plies. For single of ±45° ply, the same electrical resistance decrease caused by the shear plastic deformation of ±45° ply is observed, and the magnitude of the decrease is smaller than that of the six-ply laminate. This is because the effect of interlaminar contact resistance decrease does not exist for the single of ±45° ply. For the six of 0/90°plies, the present study shows that the electrical resistance in the through-thickness direction is decreased by the out-of-plane plastic deformation of carbon fiber and the misalignment of the plies.