High-temperature mechanical properties of thermal barrier coated SiC/SiC composites by PIP process with a new precursor polymer

作者：Luo, Zheng^*; Zhou, Xingui; Yu, Jinshan

来源：Surface and Coatings Technology, 2014, 258: 146-153.

DOI：10.1016/j.surfcoat.2014.09.038

• SiC/SiC composites
• Environmental barrier coating
• LPVCS
• High-temperature mechanical properties

Three dimensional (3D) braided silicon carbide (SiC) fiber reinforced SiC matrix (SiC/SiC) composites were fabricated by precursor impregnation and pyrolysis (PIP) process. Liquid polyvinylcarbosilane (LPVCS) with active Si-H and -CH=CH2 groups was adopted as the SiC matrix precursor. SiC/SiC composites were coated with environmental barrier coatings (EBCs) to enhance their durability and air oxidation resistance at high temperature. The fabricated SiC/SiC composites exhibited superior density and high-temperature mechanical properties. Bulk density and porosity of the composites were 2.16 g/cm(3) and 6.7%, respectively. The tensile strength of the composites was 339.7 MPa at 1300 degrees C. Tension-tension fatigue tests were conducted at frequency of 1 Hz ranging from 40 to 120 MPa at 1300 degrees C in air. Fatigue life could be divided into four regimes, low cycle regime, stable-state regime, high cycle regime and run-out regime. The microstructure as well as damage and failure mechanisms of the composites were investigated.

• 出版日期2014-11-15
• 单位中国人民解放军国防科学技术大学