Insights into fracture mechanisms and strength behaviors of two-dimensional carbon fiber reinforced silicon carbide composites at elevated temperatures
Insights into fracture mechanisms and strength behaviors of two-dimensional carbon fiber reinforced silicon carbide composites at elevated temperatures
复制标题
深入了解二维碳纤维增强碳化硅复合材料在高温下的断裂机制和强度行为
DOI：
10.1016/j.jeurceramsoc.2021.09.028
复制
发表时间：
2021-10-22
影响因子：
5.7
通讯作者：
Cheng, Tianbao
中科院分区：
文献类型：
--
作者：
Cheng, Tianbao
碳纤维增强碳化硅（C/SiC）复合材料在使用过程中经常受到热-机械-氧化耦合载荷的影响。然而，它们在超高温氧化环境下的力学性能却鲜有报道。本文提出了一种基于感应加热技术的材料在空气中超高温力学性能测试方法。首次研究了化学气相渗透法制备的二维C/SiC平织材料在高达1800℃的空气中的弯曲行为。观察到弯曲模量和强度的逆温度依赖性。阐明了导致高温下力学行为的新断裂机制。提出了不同温度下的断裂模式。建立了氧化环境下的高温断裂强度模型，与实验结果吻合较好。定量表征了影响C/SiC在高温空气中断裂强度行为的因素。
Carbon fiber reinforced silicon carbide (C/SiC) composites are usually subjected to thermal-mechanicaloxidation-coupled loads during service. However, their mechanical properties at ultra-high temperatures in oxidizing environments have rarely been reported. In this paper, a method based on the induction heating technology is proposed for testing the ultra-high-temperature mechanical properties of materials in air. The flexural behaviors of a 2D plain-weave C/SiC material prepared via chemical vapor infiltration are investigated in air up to 1800 degrees C for the first time. Inverse temperature dependences of the flexural modulus and strength are observed. New fracture mechanisms that are responsible for the mechanical behaviors at elevated temperatures are elucidated. Fracture modes at different temperatures are proposed. A high-temperature fracture strength model for oxidizing environments is developed, which is in good agreement with the experimental results. The factors affecting the fracture strength behaviors of the C/SiC in air at elevated temperatures are characterized quantitatively.