陶瓷基复合材料结构固有频率与内部损伤分析  

Analysis of Structural Natural Frequency and Internal Damage of Ceramic Matrix Composites

作　　者：汪佳辉 吴锦武[1,2] 郭小军 胡晓安 李龙彪 王海涛[5] WANG Jia-hui;WU Jin-wu;GUO Xiao-jun;HU Xiao-an;LI Long-biao;WANG Hai-tao(School of Aircraft Engineering,Nanchang Hangkong University,Nanchang 330063,China;Jiangxi Key Laboratory of Micro Aeroengine,Nanchang 330063,China;AECC Hunan Powerplant Research Institute,Hunan Zhuzhou 412002,China;College of Civil Aviation,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;The Second Construction Co.,Ltd.of China Construction First Group,Beijing 102600,China)

机构地区：[1]南昌航空大学飞行器工程学院,南昌330063 [2]江西省微小航空发动机重点实验室,南昌330063 [3]中国航发湖南动力机械研究所,湖南株洲412002 [4]南京航空航天大学民航学院,南京210016 [5]中建一局集团第二建筑有限公司,北京102600

出　　处：《失效分析与预防》2021年第3期177-183,共7页Failure Analysis and Prevention

基　　金：国家自然科学基金(51965041)。

摘　　要：通过室温条件下的循环加卸载试验,研究编织SiC/SiC复合材料固有频率特性及内部损伤演化过程。结果表明:固有频率随循环加卸载过程中峰值应力的增大而减小,通过分别定义频率衰退参数Φ与模量衰退参数D表征了复合材料固有频率与弹性模量的折减程度。基于细观力学理论对编织陶瓷基复合材料循环加卸载迟滞回线进行理论计算,理论模拟结果与试验数据良好吻合。同时,分析计算结果还发现,随着循环加卸载过程中Φ的增加,材料弹性模量衰退参数D、界面脱粘比2l_(d)/l_(c)和纤维断裂概率q均呈明显上升趋势,当陶瓷基复合材料结构固有频率衰退1%时,基体出现开裂,界面发生脱粘;当固有频率衰退4.17%时,2l_(d)/l_(c)上升至1(即完全脱粘),q增加到2.5%,这表明复合材料固有频率的变化可以反映出材料内部的损伤失效过程。Natural frequency characteristics and damage evolution of woven SiC/SiC composites were investigated under cyclic loading-unloading test at room temperature.The results show that the natural frequency decreases with the increase of peak stress during the runs,then the natural frequency and elastic modulus reduction degree of the composites were determined by defining the frequency decay parameterΦand the modulus decay parameter D,respectively.Based on the micromechanics theory,the cyclic loading and unloading hysteresis loops of woven ceramic matrix composites were calculated theoretically,and the simulation results are in good agreement with the experimental data.Besides,the analysis reveals that the modulus decay parameter D,the interfacial debonding ratio 2l_(d)/l_(c),and the fiber fracture probability q all exhibite an obvious upward trend with the increased frequency decay parameterΦ.Matrix cracking and interfacial debonding took place when the natural frequency of composites declined by 1%.Moreover,when the natural frequency decreased by 4.17%,the interfacial debonding ratio was increased to 1(that is fully debonding),and the fiber fracture probability was increased to 2.5%,which indicates that the variation of natural frequency can effectively reflect the internal damage and invalidation process of the material.

关 键 词：陶瓷基复合材料 二维编织 固有频率 迟滞回线 损伤分析 

分 类 号：TB332[一般工业技术—材料科学与工程]