抄録
Three-dimensional composites were made firstly by orientating fiber bundles in roving or rodlike shape unidirectional composites and secondarily molded with resin. To evaluate the elastic constants and the strength of the 3-D composites, an analytical method was developed adopting the orthogonal anisotropic theory of elasticity. Tensile and compressive tests on orthogonal three axis 3-D CFRP were also made, and the results of elastic constants and initial breaking strength were compared with the theoretical values. The test result showed good agreement with the analytical result. Furthermore, these mechanical properties were evaluated for 3-D composites consisting of 3 to 7-axis by using the analytical method. As the results, it was found that 7 axis were advantageous to pseudo-isotropic material, and 4 or 5 axis to anisotropic material.
