三维针刺C/SiC复合材料无纬布纤维方向对材料力学性能的影响

通过化学气相渗透法结合反应熔体浸渗法制备了三维针刺C/SiC复合材料,采用扫描电子显微镜观察材料的显微结构,并研究了无纬布纤维方向对材料力学性能的影响.结果表明,三维针刺C/SiC复合材料由O°无纬布层、短纤维胎网层、90°无纬布层以及针刺纤维束组成,无纬布层纤维方向对材料性能有显著影响.试样的拉伸强度和弯曲强度随着无纬布纤维方向与试样长度方向的夹角θ(0 ～45°)值的增大而减小,面内剪切强度和冲击韧性随θ角的增大而增大.

Effect of Direction of Fibers in the Non-woven Cloth in 3D Needled C/SiC Composites on the Mechanical Performance

The 3D needled C/SiC composites were fabricated by chemical vapor infiltration combined with liquid melt infiltration.The microstructure of the materials was investigated by scanning electron microscope.And the effect of direction of fibers in the non-woven cloth in 3D needled C/SiC composites on the mechanical performance was investigated.The results indicated that the 3D needled C/SiC composites were composed of the layers of 0°non-woven fiber cloth,short fiber web,90° non-woven fiber cloth,and needle fibers.Effects of direction of fibers in the non-woven cloth in 3D needled C/SiC composites on the mechanical performance were significant.The tensile and flexural strength of the test samples were decreased with increasing the value of θ(0-45°) that is the angle between the direction of fibers in the non-woven cloth and the direction along the length of the samples.The in-plane shear strength and impact-toughness were increased with increasing the value of θ.