Mechanical Properties and Oxidation Behaviors of Self-Healing SiCf/SiC-SiBCN Composites Exposed to H_(2)O/O_(2)/Na_(2)SO_(4)Environments  

作　　者：Suya Ji Bin Liang Chenglong Hu Shengyang Pang Rida Zhao Jian Li Sufang Tang 

机构地区：[1]Shi-Changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang,110016,China [2]School of Materials Science and Engineering,University of Science and Technology of China,Shenyang,110016,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2023年第11期1909-1923,共15页金属学报（英文版）

基　　金：the National Natural Science Foundation of China(Grant Nos.52188101,U20A20242,52022101 and 52272075);the Research Fund of Youth Innovation Promotion Association of Chinese Academy of Sciences,China(Grant No.2021190);the directional institutionalized scientific research platform relies on China Spallation Neutron Source of Chinese Academy of Sciences and the National Key R&D Program of China(Grant No.2021YFA1500804).

摘　　要：The oxidation behaviors and their influence on the mechanical properties of self-healing SiCf/SiC-SiBCN composites were investigated in H_(2)O/O_(2)and H_(2)O/O_(2)/Na_(2)SO_(4)environments at 1200‒1350℃for 100 h.As the temperatures increase from 1200 to 1350℃,the oxidation rate constants increase from 0.45×10^(–7)to 1.58×10^(–7)mg^(2)/(mm^(4) h)in H_(2)O/O_(2),and from 1.02×10^(–7)to 3.42×10^(–7)mg^(2)/(mm^(4) h)in H_(2)O/O_(2)/Na_(2)SO_(4).The involvement of Na_(2)SO_(4)leads to the formation of a loose lamellar oxide layer,the breakage of the SiBCN/CVI-SiC interface and the decrease in the oxide viscosity,thus accelerating the oxidation of the composites.The composites show the maximum retention rate of strength(102%,535.71 MPa)after oxidation in H_(2)O/O_(2)at 1200℃due to the good self-healing capacity of the produced glass,while the minimum(82%,430.56 MPa)in H_(2)O/O_(2)/Na_(2)SO_(4)at 1350℃caused by the severe microstructural corrosion derived from Na_(2)SO_(4).

关 键 词：SiCf/SiC-SiBCN composite Mechanical property Oxidation Chemical vapor infiltration and polymer infiltration and pyrolysis(CVI-PIP) SELF-HEALING 

分 类 号：TG142.1[一般工业技术—材料科学与工程] TG172[金属学及工艺—金属材料]