Influence of Oxidation Damages on Mechanical Properties of SiC/SiC Composite Using Domestic Hi-Nicalon Type SiC Fibers

Enze Jin; Denghao Ma; Zeshuai Yuan; Wenting Sun; Hao Wang; Jiajia Zhang; Xiaodong Gong; Lina Huang; Botao Han; Xin Sun; Zhihai Feng; Junping Li

doi:10.1155/2020/8840963

Influence of Oxidation Damages on Mechanical Properties of SiC/SiC Composite Using Domestic Hi-Nicalon Type SiC Fibers

Scanning. 2020 Dec 8:2020:8840963. doi: 10.1155/2020/8840963. eCollection 2020.

Authors

Enze Jin¹, Denghao Ma¹, Zeshuai Yuan¹, Wenting Sun¹, Hao Wang¹, Jiajia Zhang¹, Xiaodong Gong¹, Lina Huang¹, Botao Han¹, Xin Sun¹, Zhihai Feng¹, Junping Li¹

Affiliation

¹ Key Laboratory of Advanced Functional Composites Technology, Aerospace Research Institute of Materials & Processing Technology, Beijing 100076, China.

Abstract

Here, we show that when the oxidation treatment temperature exceeded 600°C, the tensile strength of SiC/SiC begins to decrease. Oxidation leads to the damages on the PyC fiber/matrix interface, which is replaced by SiO₂ at higher temperature. The fracture mode converts from fiber pull-out to fiber-break as the fiber/matrix interface is filled with SiO₂. Oxidation time also plays an important role in affecting the tensile strength of SiC/SiC. The tensile modulus decreases with temperature from RT to 800°C, then increases above 800°C due to the decomposition of remaining CSi _x O _y and crystallization of the SiC matrix. A special surface densification treatment performed in this study is confirmed to be an effective approach to reduce the oxidation damages and improve the tensile strength of SiC/SiC after oxidation.