Cf/铯榴石陶瓷基复合材料的界面调控、断裂和蠕变损伤机制

Pollucite derived from geopolymer possess many prominent properties of heat and corrosion resistance, low density and environmentally friendly nature, etc. Meanwhile, pollucite-based composites with high strength and toughness can be obtained by the incorporation of fibers, which have wide potential applications in the area of aeronautics and astronautics, metallurgy, chemical engineering, and national defense, etc. However, there are only limited investigations on the pollucite based composites derived from geopolymer till now, and little work has been conducted on the high temperature damage mechanism of this kind of composites. In this project, matrix doping and carbon fiber modification will be carried out, in order to improve the interface compatibility between fiber and pollucite matrix. Geopolymerization and crystallization mechanisms of the mixed alkaline cations-based geopolymer will be researched. Interface microstructure, mechanical properties and creep behavior will be systematically investigated during the post-heat treatment and service temperature. The fracture and creep damage mechanism of the composites will be revealed. The research can achieve optimized property design of the carbon fiber reinforced pollucite composites and reveal the high-temperature damage mechanisms of this kind of composite. Meanwhile, the relevant results will provide theoretical and technical supports for the optimization of Cf/pollucite composites and their engineering applications targeted for high-temperature heat-resistant components and will reveal their failure mechanisms at elevated temperature.

铝硅酸盐聚合物转化制备铯榴石陶瓷材料具有轻质、耐热、耐腐蚀、环境友好等优点，通过纤维强韧化可获得强度与韧性大幅度提高的铯榴石陶瓷基复合材料，在航空航天、冶金、化工和国防等领域具有潜在的应用前景。国内外在采用该技术制备纤维强韧铯榴石陶瓷基复合材料及其高温损伤机制的研究仍很少。本申请拟从基体调控和碳纤维表面改性两方面入手实现纤维/基体间的界面相容性匹配，将系统研究复合离子激发铝硅酸盐聚合物的聚合机理和陶瓷化机制、复合材料在后续处理与服役环境下界面组织结构、室温和高温力学性能及其高温蠕变行为的演化规律，揭示其断裂和蠕变损伤机理。该研究对进一步优化该复合材料体系，揭示其高温损伤机制，具有重要学术价值，也会为其在高温防热、高温构件等领域的工程应用提供理论和数据支持。

碳纤维增强铝硅酸盐聚合物转化制备碳纤维增强铯榴石陶瓷基材料的制备工艺简单、成本低的优势，所制备陶瓷基复合材料具有密度低、耐热、耐腐蚀等特点，因此在航空航天、冶金、化工和国防等领域具有潜在的应用前景。本项目通过离子掺杂实现铯榴石热膨胀系数的宽范围调控，使之与增强相碳纤维相匹配，指导设计新型绿色快速制造碳纤维增强铯榴石陶瓷基复合材料，系统研究了复合激发离子对于铝硅酸盐聚合物聚合进程和热演化过程的影响规律，以及复合材料的界面结构、力学性能与断裂行为等的演变规律。研究结果表明，通过离子掺杂可显著降低铯榴石生成温度并实现热膨胀系数调控，不仅利于碳纤维增强铯榴石复合材料的制备，为其在高温防热、高温构件等领域的工程应用提供理论和数据支持。