纤维束丝数对平纹编织C/SiC复合材料力学性能的影响

通过对2种丝束平纹编织碳纤维布增强SiC（C/SiC）复合材料的力学性能实验,研究了纤维束丝数（1 k和3 k）对复合材料性能的影响.实验结果表明：1 k C/SiC复合材料的拉伸模量、拉伸强度、压缩模量、压缩强度、面内剪切强度和弯曲强度分别为90.8 GPa,281.8 MPa,135.8 GPa,452.2 MPa,464.3 MPa和126.8 MPa,分别比3 k C/SiC高39%,15.8%,25%,132%,29.3%和30.2%.纤维束粗细不同是导致纤维束弯曲度和复合材料孔隙率差异的主要原因,对压缩强度的影响最大,对拉伸强度的影响最小.

EFFECT OF YARN COUNTS ON MECHANICAL PROPERTIES OF PLAIN WEAVE C/SIC COMPOSITES

The effect of the yarn counts on mechanical properties of the woven carbon cloth with two types of tow(1 k and 3 k) reinforced silicon carbide(C/SiC) composites was investigated by the mechanical tests.The experimental results indicate that the 1 k yarn C/SiC composite shows greater stiffness and strength than the 3k yarn composite.The tensile elastic modulus,tensile strength,compression modulus,compression strength,shear strength and bending strength of the 1 k C/SiC composite are 90.8 GPa,281.8 MPa,135.8 GPa,(452.2 MPa),464.3 MPa and 126.8 MPa,and exceed 39%,15.8%,25%,132%,29.3% and 30.2% of the 3 k C/SiC composite respectively.Unequal yarn thickness causes differences in the warp waviness and the void volume fraction in the composites.The warp waviness and the void volume fraction have a severe effect on the compression strength and the least effect on tensile strength.