薄层化碳布缝合碳/碳复合材料制备与性能

Preparation and properties of spreading carbon cloth stitched C/C composites

为获得高性能、低成本碳/碳复合材料,以商用级T700大丝束薄层化碳纤维展宽平纹布和航空航天级T300小丝束碳纤维缎纹布为原材料制备缝合预制体,采用化学气相沉积工艺方法制备了一系列缝合碳/碳复合材料,对材料的气相致密化特征、微观结构特征和力学性能进行了测试与分析。研究结果表明,碳布规格和缝合间距对材料气相致密化效果和力学性能有较大影响。当选用T700-12 K、展宽16 mm大丝束纤维编织的面密度100 g/m^(2)的平纹布为原材料且预制体缝合间距为5 mm×5 mm时,制备的密度为1.781 g/cm^(3)薄层化碳布缝合碳/碳复合材料表现出良好的气相沉积工艺适应性和优异的力学性能,材料拉伸强度、压缩强度、弯曲强度和层间剪切强度高达342.9 MPa、285.5 MPa、328.4 MPa和15.2 MPa。通过商用级大丝束薄层化碳纤维的应用,大幅降低了高性能碳/碳复合材料的原材料成本,且制备的碳/碳复合材料性能达到了国际先进水平。

In order to obtain high-performance and low-cost C/C composites,a series of preforms stitched with commercial grade large tow spreading carbon fiber cloth or aerospace grade small tow carbon fiber cloth were prepared.The carbon cloth stitched C/C composites were prepared by chemical vapor deposition(CVD),and the densification characteristics,microstructure features and mechanical properties of stitched C/C composites were characterized and discussed.The investigation results show that the types of carbon cloth and stitching density have obvious effects on the densification and mechanical properties of stitched C/C composites.When the type of preform selects key characteristics as spreading fiber cloth T700-12 K-100 g and stitching density 5 mm×5 mm,the values of tensile strength,compression strength,flexural strength and interlaminar shear strength for stitched C/C composites(1.781 g/cm3)reach 342.9 MPa、285.5 MPa、328.4 MPa and 15.2 MPa respectively,which are the international advanced level.The cost of high-performance C/C composites is greatly reduced by using spreading carbon cloth.