The aircraft engine firewall prevents the spread of flames and high temperatures to other parts of the aircraft, curbing fire escalation and buying critical time for crew members to respond to emergencies, thereby reducing risks to aircraft structures and personnel. It also effectively blocks heat transfer from the engine, avoiding performance degradation and material aging in adjacent structures due to prolonged thermal exposure, thus ensuring the stability and safety of surrounding equipment and structures. This study addresses issues such as heavy weight, installation challenges, high production and maintenance costs, and lengthy cycles associated with existing aviation engine firewall materials by developing and evaluating the properties of Al₂O_3f/Al₂O₃-SiC ceramic matrix composites. Experimental results demonstrate that the Al₂O_3f/Al₂O₃-SiC composite exhibits excellent mechanical properties, including a tensile strength of 103 MPa, tensile modulus of 45.2 GPa, compressive strength of 256 MPa, compressive modulus of 106 GPa, flexural strength of 189 MPa, flexural modulus of 106 GPa, and interlaminar shear strength of 12.1 MPa. Damage modes involve matrix cracking, interfacial layer delamination, fiber pull-out, and fiber bundle fracture. Additionally, the composite demonstrates superior flame penetration resistance. Compared to conventional titanium alloy firewall materials, it achieves a weight reduction exceeding 40%.

Continuous silicon carbide fiber reinforced silicon carbide ceramic matrix composite (SiC/SiC) have the advantages of low density, high temperature resistance, low tritium permeability and excellent irradiation stability, and have broad application prospects in aviation, aerospace, nuclear energy and other fields. This article focuses on the problems of long cycle, high porosity, and easy oxidation of SiC/SiC composite materials prepared by PIP process. Aluminum oxide ceramics are introduced into the matrix through slurry pre-impregnation process to form SiC/Al₂O₃-SiC composite matrix composite materials. The preparation process, microstructure, and mechanical properties of the composite materials are systematically characterized. The analysis results show that the preparation period of SiC/Al₂O₃-SiC composite is significantly shorter than that of the traditional PIP process, and the porosity of the composite is significantly reduced from about 11.6% to 6%, the tensile strength is 316.5MPa, increased by 12.3%, and the bending strength is equivalent to that of SiC/SiC, but the interlaminar shear strength is lower, only 16.3MPa, which needs to be further improved.

continuous alumina fiber is the main raw material of a new generation of hightemperature resistant hot-end components due to its high melting point, low thermal conductivity, good insulation, strong resistance to chemical erosion and high specific strength. This material is used to prepare high-temperature-resistant, high-strength, anti-heat-insulating ceramic matrix composite materials, which are widely used in high-end fields such as aviation, aerospace, shipbuilding, thermoelectricity, petrochemicals, semiconductors, automobiles, and high-temperature furnaces. Alumina fiber and its composite materials abroad have been commercialized and implemented in component applications. Significant strides has been made domestically in this field over the past decade by transitioning from basic research to applied research. This paper summarizes the research progress on preparation, industrial layout of alumina fiber and its composites.Finally, the key problems and future development emphases of the alumina fiber and its composites are proposed.