摘要
为提高对SiCf/SiC复合材料在服役中失效机制的理解以及更合理地设计该类材料,通过声发射探测结合两种力学加载实验对该材料的损伤过程进行了评估与分析,并利用光学显微镜和扫描电子显微镜等手段对其损伤状态的演变进行了详细的表征和总结。实验结果表明,声发射技术可有效评估SiCf/SiC复合材料的损伤程度,并用以分析特定加载应力水平下的损伤发展。研究表明:裂纹在较低的加载应力下(<80 MPa)易在材料的原生缺陷附近或多种组分的边界处萌生,但对材料自身强度影响较小;较高的加载应力(≥100 MPa)则会使材料产生大尺度开裂,并与纤维发生相互作用进而降低材料的稳定性。SiCf/SiC复合材料在递增的加载应力下会产生5种开裂形式以及纤维的断裂拔出和界面的脱粘等损伤行为。
To further understand the failure mechanism of SiCf/SiC composites in service and more reasonably design such materials, acoustic emission detection combined with two kinds of mechanical loading tests was performed on the material to evaluate and analyze its damage process. Damage states were characterized and summarized by optical microscopy and scanning electron microscopy. Experimental results indicate that the acoustic emission technology can efficiently evaluate the damage extent and analyze the damage development of SiC_f/SiC composites subjected to specific stress levels. Under low stresses(<80 MPa), cracks were prone to initiate near the original defects or at the boundaries of various components in the materials, but they had little effect on the strength of the material. Higher stresses(≥100 MPa) caused the material to crack on a large scale and cracks interacted with the fibers to degrade the stability of the material. The increasing loading stresses resulted in 5 types of cracks and damage behaviors such as fiber pull-out and interfacial debonding in SiC_f/SiC composites.
作者
薛玉冬
胡建宝
杨金山
周海军
张翔宇
丁玉生
董绍明
XUE Yudong;HU Jianbao;YANG Jinshan;ZHOU Haijun;ZHANG Xiangyu;DING Yusheng;DONG Shaoming(State Key Laboratory of High Performance Ceramics and Superfine Microstructure(Shanghai Institute of Ceramics,Chinese Academy of Sciences),Shanghai 200050,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2020年第3期89-97,共9页
Materials Science and Technology
基金
中国科学院前沿科学重点研究项目(QYZDY-SSW-JSC031)
中国科学院重点部署项目(ZSEW-CN-2017-1)。
