针刺工艺参数对炭布网胎增强C/C材料力学性能的影响

采用机械针刺技术, 研究了针刺密度、针刺深度对原位针刺增强碳布网胎迭层预制体结构C/C材料力学性能的影响. 结果表明, 采用高的针刺密度和针刺深度参数, 可获得高的预制体密度和纤维体积分数, 针刺密度和针刺深度对材料层间剪切性能的影响程度比对压缩、弯曲性能的影响程度大, 采用一定密度的碳布网胎时, 在一定范围内, 提高针刺密度和深度能提高材料的力学性能,当针刺密度控制在20～50针/cm²、针刺深度控制在12～16mm时, C/C材料力学性能随两针刺参数值升高而提高; 当针刺密度控制在30针/cm²时, C/C材料弯曲及X-Y向压缩强度分别达到137.68、224MPa, 剪切强度达到15.5MPa, 针刺深度为12mm时, 材料弯曲及X-Y向压缩强度分别达到134.24、213.2MPa, 为较佳的针刺工艺参数.

Influence of Needle-punching Processing Parameters on Mechanical Properties of C/C Composites Reinforced by Carbon Cloth and Carbon Fiber Net

Effect of needle-punching processing parameters on carbon-carbon (C-C) composites reinforced by carbon cloth and carbon fiber net was studied by a mechanical needling equipment in the thickness direction of perform. It is shown that high values of needle-punching density (ND) and punching depth (PD) lead to high values of perform density and fiber volume fraction, both ND and PD have larger effect on interlaminar shear strength (ILSS) than on compression strength and bending strength of C-C. The interlaminar shear strength, tensile strength, and bending strength of C-C all increase lineally with increasing punching density from 20 to 50punch/cm², also increase with increasing punching depth range from 12 to 16mm.The optimized ND parameters are 30punch/cm², which result in 15.5MPa of ILSS, 137.68MPa of bending strength and 224MPa of X-Y direction compression strength, respectively. The optimized PD parameters are 12mm, which result in 134MPa of bending strength and 213.2MPa of X-Y direction compression strength, respectively.