2.5D机织C_(f)/Al复合材料热残余应力与热变形细观力学分析  

Micromechanical FE analysis on thermal residual stress and shrinkage behavior of 2.5D woven C_(f)/Al composites

作　　者：童德 蔡长春[1] 王振军[1] 刘燕武 张益豪 余欢[1] 徐志锋[1] TONG De;CAI Changchun;WANG Zhenjun;LIU Yanwu;ZHANG Yihao;YU Huan;XU Zhifeng(School of Aeronautical Manufacturing Engineering,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]南昌航空大学航空制造工程学院,南昌330063

出　　处：《航空材料学报》2022年第2期73-82,共10页Journal of Aeronautical Materials

基　　金：国家自然科学基金(52165018,51765045);航空科学基金(2019ZF056013);江西省自然科学基金重点项目(20202ACBL204010);国防基础科研计划(JCKY2018401C004)。

摘　　要：采用细观力学数值模拟与热性能实验结合的方法,研究2.5D机织C_(f)/Al复合材料降温热变形行为和热残余应力分布。根据解析法计算的纱线轴/横向热膨胀性能和纱线空间分布结构,建立复合材料细观力学有限元模型,计算得到的宏观热应变-温度曲线与热变形实验曲线吻合较好。复合材料制备后经纱和纬纱主要处于残余压应力状态,且纬纱表现出较高的残余应力水平;基体合金则主要处于残余拉应力状态,最大拉应力出现在经纱界面处并导致经纱与纬纱之间的区域出现局部界面脱粘,降低热残余应力是改善复合材料力学性能的重要技术手段。2.5D woven C_(f)/Al composites were fabricated by vacuum-assisted pressure infiltration method. Thermal shrinkage behavior and residual stress of the composites were investigated using micromechanical analysis and experimental method. The thermal expansion properties of yarn along longitudinal and transverse direction were evaluated by analytical method. Based on the yarn’s structural characteristic, the micromechanical finite element models of composites were established. The calculated macroscopic thermal strain-temperature curve from micromechanical simulation agrees well with the thermal shrinkage curve from the experiments. The simulation results indicate that the warp and weft yarns are in compressive stress state, and the residual stress on weft yarns are higher than that on the warp yarns. However, the matrix alloy is mainly in tensile stress state, and the maximum tensile stress occurs in the matrix alloy near warp yarn’s surface. The over high residual stress between the warp and weft yarns lead to local interface debonding. It is an important technical approach to reduce the residual stress in order to improve the mechanical properties of composites.

关 键 词：2.5D机织 C_(f)/Al复合材料 残余应力 细观力学 有限元分析 

分 类 号：TB333[一般工业技术—材料科学与工程]