考虑分层损伤的平纹编织SiC/SiC弯曲失效模拟  

Flexural Failure Simulation of Plain Woven SiC/SiC Considering Delamination Damage

作　　者：冯雨春 张盛[1,2] 高希光[1,2] FENG Yu-chun;ZHANG Sheng;GAO Xi-guang(Key Laboratory of Aero-Engine Thermal Environment and Structure,Ministry of Industry and Information Technology,College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;Jiangsu Province Key Laboratory of Aerospace Power System,College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)

机构地区：[1]南京航空航天大学能源与动力学院、航空发动机热环境与热结构工业和信息化部重点实验室,江苏南京210016 [2]南京航空航天大学能源与动力学院、江苏省航空动力系统重点实验室,江苏南京210016

出　　处：《推进技术》2023年第4期241-249,共9页Journal of Propulsion Technology

基　　金：南京航空航天大学研究生创新基地(实验室)开放基金(kfjj20200210);中国博士后科学基金(2021M691566)。

摘　　要：平纹编织SiC/SiC是航空发动机热端部件的理想材料,由于其层间性能较弱,在进行力学行为和失效机理研究时需要考虑材料分层损伤的影响。采用试验和数值模拟相结合的方法,研究了平纹编织SiC/SiC复合材料在四点弯曲下的失效模式和破坏过程,通过数字图像相关法(DIC)技术实时观测试件分层损伤萌生和扩展过程。试验结果表明,分层破坏是复合材料四点弯曲最主要的失效形式。进一步,基于内聚力模型预测了平纹编织SiC/SiC复合材料梁的弯曲强度、分层萌生及扩展。预测结果与试验吻合较好,说明本文建立的数值模型是可行的。对内聚力模型中的参数进行研究,计算结果表明,法向应力极限值对弯曲曲线的初始斜率和峰值载荷均有一定的影响,而剪切应力极限值以及拉伸断裂能只对弯曲极限载荷有影响,剪切断裂能对数值模拟影响较小,失效载荷预测误差小于10%。Plain woven SiC/SiC is an ideal material for hot-end components of aero engine.Due to the weak interlayer performance,the study of mechanical behavior and failure mechanism needs to consider the effect of delamination damage.Through experiments and numerical simulations,the failure mode and failure process of plain woven SiC/SiC composites under four-point flexure were studied,and the delamination initiation and expansion process of the specimen were observed in real time through Digital Image Correlation(DIC)technology.The test results show that delamination failure is the main failure mode of four-point flexure of composites.Furthermore,the flexural strength,delamination initiation and expansion of plain woven SiC/SiC composite beams were predicted based on the cohesivezone model.The predicted results are in good agreement with the experiments,indicating that the numerical model established in this paper is feasible.The parameters in the cohesive zone model were studied.The calculation results show that the maximum normal stress has a certain influence on the initial slope and peak load of bending curve,while the maximum shear stress and tensile fracture energy only had an influence on the bending peak load,and the shear fracture energy had little influence on the numerical simulation,and the failure load prediction error is less than 10%.

关 键 词：平纹编织SiC/SiC 分层损伤 内聚力模型 四点弯曲 热端部件 

分 类 号：TB332[一般工业技术—材料科学与工程]