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本研究的目的是开发一种在中等温度范围(371～649℃)内,抗氧化性能得到增强的碳/碳(C/C)复合材料。通过在C/C复合材料(CCC)固化前引入纳米相,通过阻止复合材料氧化过程,以维持并提高材料的机械强度。三种树脂系统:Lonza公司的低、中性粘度氰酸酯(CE),型号为PT-15和PT-30,以及Hitco 公司的酚醛,型号围为134A;同时利用三种类型的纳米颗粒:化学改性蒙脱石(MMT)有机金属粘土、多面体低聚氧化硅(POSS),纳米碳纤维得到CCC。利用广角X射线衍射装置(WAXD)和透射电子显微镜(TEM) 来确定分散度。对碳化及致密化分别制备了具有六种不同纳米结构体系的CCC,对这六种材料及一种基本 Hitco CC139分别在371℃和649℃的氮气中进行了24h的热老化处理。然后将这些材料置于加热的空气中达8h,用来模拟热-氧化的情形。最后测定了这些C/C纳米复合材料的力学性能如:抗拉强度和模量、泊松比和层间剪切强度等,并与基本的CCC做了比较。
The purpose of this study was to develop a carbon / carbon (C / C) composite with enhanced oxidation resistance at a moderate temperature range of 371-649 ° C. By introducing a nano-phase prior to the C / C composite (CCC) curing, the mechanical strength of the material is maintained and enhanced by preventing the composite oxidation process. Three resin systems: Lonza’s low and neutral viscosity cyanate ester (CE), model number PT-15 and PT-30, and Hitco’s phenolic model 134A; three types of nanoparticles are used at the same time: Chemically modified montmorillonite (MMT) organometallic clay, polyhedral oligomeric silica (POSS), carbon nanofibers get CCC. Dispersion was determined using Wide Angle X-ray Diffraction (WAXD) and Transmission Electron Microscopy (TEM). CCC with six different nanostructured systems were prepared for carbonization and densification, respectively, and these six materials and a basic Hitco CC139 were thermally aged for 24 h in nitrogen at 371 ° C and 649 ° C, respectively. These materials were then placed in heated air for 8 h to simulate thermo-oxidative conditions. Finally, the mechanical properties of these C / C nanocomposites such as tensile strength and modulus, Poisson’s ratio and interlaminar shear strength were measured and compared with the basic CCC.