抄録
This paper deals with the mechanism of electrical resistance change observed after delamination cracking of a thick Carbon Fiber Reinforced Polymer (CFRP) laminate. In a previous paper, the current shut-off caused by the delamination crack increased the electrical resistance for a thin laminate, and the effect of piezoresistance caused by the residual strain relief was small compared with the shut-off effect. For the thick CFRP, a dent is made because of the high indentation compression load at the loading point. The present paper measures the effect of the dent experimentally and estimates the electrical resistance increases caused by the shut-off effect and piezoresistance effect using Finite Element Method (FEM) analyses. The estimates are compared with the experimental results of the thick CFRP laminate. As a result, it is established that the effect of the dent (which causes a decrease of electrical resistance) is larger than the effect of the shut-off (which causes an increase of electrical resistance) for the thick CFRP laminate.
