摘要
文摘为了利于大型构件的制备,采用浆料浸渍工艺,以Nextel 720连续氧化铝纤维增韧,通过一次烧结过程制备了Al_(2)O_(3)/Al_(2)O_(3)陶瓷基复合材料。测试了复合材料的物理及力学性能,并采用光学显微镜、SEM对试样的微观形貌进行了表征。结果表明:复合材料的体积密度为2.64 g/cm^(3),显气孔率为26%,材料基体呈现典型的多孔结构特征;室温及1 200℃,复合材料厚度方向的热导率分别为3.49及2.04 W/(m·K);200~1 200℃,复合材料面内方向的热膨胀系数为(4.7~7.1)×10^(-6)/K;复合材料室温、1 100及1 200℃拉伸强度分别为202.4、222.4及228.4 MPa,试样断面纤维拔出明显;室温弯曲强度为200.5 MPa,试样发生韧性断裂;层剪强度为21.0 MPa。制备的材料主要性能与美国ATK-COI陶瓷公司的同类型材料相当,部分力学性能更优异。
Al_(2)O_(3)/Al_(2)O_(3)composite was prepared by slurry infiltration method in one processing cycle using Nextel 720 alumina fiber as reinforcement in order to facilitate the preparation of large components.Physical and mechanical properties of the composite were evaluated and the cross section and microstructure were studied by optical microscope and SEM.The results show that the bulk density of Al_(2)O_(3)/Al_(2)O_(3)composite is 2.64 g/cm^(3) and the apparent porosity is 26%,porous nature of the matrix is evident.The transverse thermal conductivity from room temperature to 1 200℃ is 3.49 to 2.04 W/(m·K) for the prepared composite.The CTE in thickness direction from 200℃ to 1 200℃ is 4.7×10to 7.1×10^(-6)/K.The in-plane tensile strength at room temperature,1 100℃ and 1200℃ are 202.4 MPa,222.4 MPa and 228.4 MPa,respectively.It is clearly observed that many fibers are pulled out of the ceramic matrix from the optical micrographs and SEM image of fracture surface of tensile specimen.Flexure strength of Al_(2)O_(3)/Al_(2)O_(3)composite at room temperature is 200.5 MPa,and the sample shows ductile fracture.Interlaminar shear strength of Al_(2)O_(3)/Al_(2)O_(3)composite is 21.0 MPa.The main properties of the prepared materials are equivalent to the same type of material from ATK-COI Ceramic,USA,and some mechanical properties are better.
作者
杨瑞
董禹飞
赵文青
杨金华
焦健
YANG Rui;DONG Yufei;ZHAO Wenqing;YANG Jinhua;JIAO Jian(National Key Laboratory of Advanced Composites,AECC Beijing Institute of Aeronautical Materials,Beijing 100095;Key Laboratory of Advanced Corrosion and Protection for Aviation Materials,AECC Beijing Institute of Aeronautical Materials,Beijing 100095)
出处
《宇航材料工艺》
CAS
CSCD
北大核心
2022年第5期60-65,共6页
Aerospace Materials & Technology
关键词
氧化铝
陶瓷基复合材料
浆料浸渍工艺
物理性能
力学性能
Alumina
Ceramic matrix composite
Slurry infiltration method
Physical property
Mechanical property
