2.5D机织浅交弯联复合材料数字单元建模分析  

Digital element modelling and analysis of 2.5D woven shallow cross bending composites

作　　者：王宏越 王兵[1] 方国东[1] 孟松鹤[1] WANG Hongyue;WANG Bing;FANG Guodong;MENG Songhe(National Key Laboratory of Science and Technology on Advanced Composites in Special Environments,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]哈尔滨工业大学特种环境复合材料技术国家级重点实验室,哈尔滨150001

出　　处：《航空学报》2023年第9期214-226,共13页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(12090034);中国博士后科学基金(2021M701009);黑龙江省自然科学基金(YQ2021A004)。

摘　　要：2.5D机织浅交弯联复合材料具有优良的力学性能及结构整体性,现已广泛应用于航空航天结构中,正确表征材料内部发生挤压或偏转变形的纤维结构形态是从微细观角度研究材料性能的关键。数字单元法是模拟材料内部纤维束形态的有效途径,但得到的纤维束形态依赖于选取的仿真参数。基于2.5D机织浅交弯联SiO2f/SiO2复合材料的Micro-CT观测,利用ABAQUS软件建立了材料的数字单元有限元模型,施加温度载荷及边界约束,模拟织物变形过程,并且提取织物变形后的数字单元特征信息,结合纤维束中心路经及横截面形状离散算法得到纤维束的结构形态。通过分析选取的单元类型、数字单元赋予的弹性性能、单元数、摩擦系数对模拟结果的影响,确定选取模拟参数的主要原则,得到了能反映该材料纱线变形特征的几何模型,并且与Micro-CT观测结果吻合。该方法具有普适性,可指导类似织物复合材料的数字单元建模。2.5D woven shallow cross bending composites have been widely used in aerospace structures because of their excellent mechanical properties and structural integrity.Correctly characterizing the fiber structure with extrusion or deflection deformation is the key to studying the materials properties in the micro-and meso-scale.The digital element method is an effective way to simulate the internal fiber bundle shape of the woven composites;however,the obtained results depend on the selection of the simulation parameters.Based on the Micro Computed Tomography(Micro-CT)observation of 2.5D woven shallow cross bending SiO2f/SiO2 composites,a digital element finite element model of the materials is established using the Abaqus software.The temperature load and boundary constraints are applied to the simulation of the fabric deformation process,and the digital element characteristic information after fabric deformation is extracted.Combining the central path and cross-section shape discretization algorithm of the fiber bundles,we obtain the structural shape of the fiber bundles.Analysis of the influences of the selected element type,the elastic properties of the digital element,the number of elements and the friction coefficient on the simulation results determines the main selection principles of the simulation parameters.A geometric model that can reflect the yarn deformation characteristics of the woven composites is obtained,which is consistent with the CT observation results.This method is universal and can guide the digital element modelling of similar fabric composites.

关 键 词：机织复合材料 数字单元法 Micro CT切片 高保真建模 几何重构 

分 类 号：V258[一般工业技术—材料科学与工程]