摘要
将复合球模型导入损伤力学模型中,模拟了材料在高温环境下受拉和受压损伤时的细观演化过程;推导了材料损伤参数与界面相参数之间的函数关系。研究表明,当外加载荷小于材料损伤临界值、介于材料损伤临界值和最大承载值之间时,不论材料承受拉载还是压载,都存在无损伤演化的线弹性阶段和微裂纹扩展区逐渐增大的损伤强化阶段;若应力达到最大承载值后仍继续增大,材料损伤将过渡到损伤局部化阶段,损伤局部化的连续也就是材料宏观裂纹萌生的开始。
In order to investigate the thermal damage mechanism of Si3N4 bonded SiC refractory ceramics, the damage evolution of the materials under tension and pressure at high temperature was simulated on a micromechanical scale, which was based on a composite sphere model incorporated with the damage mechanics model. And the function relationship between the damage parameters and the interface parameters was deduced. The analyses suggest that there is a linear elastic phase without damage evolution when the load is less than the critical value;and a damage strengthening phase with increasing micro-crack expanding region when the load is higher than the critical and lower than the maximum. The above facts are true whether the material is under tension or pressure. If the load keeps increasing, the damage localization phase would occur, in which the damage development is the beginning of the macroscopic cracking of the material. The results provide references for preventing these materials from fatigue fracture at high temperature.
作者
袁虎
杨自春
赵爽
孙文彩
YUAN Hu;YANG Zichun;SHUANG Zhao;SUN Wencai(Institute of High Temperature Structural Composite Materials for Naval Ship,Naval University of Engineering,Wuhan 430033,China)
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2019年第1期102-106,152,共6页
Journal of Materials Science and Engineering
基金
国家自然科学基金资助项目(51509254)
大学科研发展基金资助项目(20160135
425517K153)
关键词
耐火陶瓷
细观演化
受热损伤
refractory ceramic
mesoscopic evolution
thermal damage
