二軸引張負荷下における一方向CFRPの破壊特性

To clarify biaxial fracture properties of the unidirectional carbon-fiber-reinforced plastic (CFRP) composites, a cruciform specimen with two symmetric rectangular flat dents in thickness direction was developed, and tensile tests were carried out under 0º 90º loadings. The showed three modes, namely transverse crack (TC), fiber break (FB), mixture TC FB modes (TC&FB). According to strain measurement result, regardless magnitude occurring direction, TC- TC&FB-modes occurred when positive, FB-mode it negative. It concluded that along zero, straight line slope ν21 (Poisson’s ratio 1-direction stressed 2-direction) can divide stress data other modes. A coefficient determining elliptical rotation angle failure envelope introduced, assuming occurs at levels comparable uniaxial strength. envelopes given by correspond average data.