Effects of interfacial residual stress on mechanical behavior of SiCf/SiC composites

Journal of Advanced Ceramics

Guofeng Cheng¹  Jinshan Yang²  Xiaowu Chen²  Chunjin Liao²  Xiangyu Zhang²  Shaoming Dong²  Jianbao Hu² 

[1] Analysis and Testing Center for Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai, China;State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai, China;Structural Ceramics and Composites Engineering Research Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai, China;

关键词: ceramic matrix composites;    Raman spectroscopy;    mechanical properties;    residual stress;   

DOI  :  10.1007/s40145-021-0519-5

来源: Springer

【 摘 要 】

Layer-structured interphase, existing between reinforcing fiber and ceramics matrix, is an indispensable constituent for fiber-reinforced ceramic composites due to its determinant role in the mechanical behavior of the composites. However, the interphase may suffer high residual stress because of the mismatch of thermal expansion coefficients in the constituents, and this can exert significant influence on the mechanical behavior of the composites. Here, the residual stress in the boron nitride (BN) interphase of continuous SiC fiber-reinforced SiC composites was measured using a micro-Raman spectrometer. The effects of the residual stress on the mechanical behavior of the composites were investigated by correlating the residual stress with the mechanical properties of the composites. The results indicate that the residual stress increases from 26.5 to 82.6 MPa in tension as the fabrication temperature of the composites rises from 1500 to 1650 °C. Moreover, the increasing tensile residual stress leads to significant variation of tensile strain, tensile strength, and fiber/matrix debonding mode of the composites. The sublayer slipping of the interphase caused by the residual stress should be responsible for the transformation of the mechanical behavior. This work can offer important guidance for residual stress adjustment in fiber-reinforced ceramic composites.

【 授权许可】

CC BY