LCM中织物变形与多尺度渗透性交互作用机理

The permeability of fabric is a very important parameter in Liquid Composite Molding (LCM), but fabric deformation will result in change of original internal structure and formability and micro-porous structure of fabrics/textiles, thereby causing local permeability change in fabrics, which will ultimately affect the resin flow and impregnation process and the quality of composite products. Adopting the fiber kinematic method and fabric deformation characterization method, the proposed project will discuss the multivariate deformation mechanism of fabrics and preforms in LCM process, and explore the distribution and evolution of fiber assembly structure and pore structure under fabric deformation based on multi-scale(macro-meso) analysis method combined with the fabric formability and fiber kinematic methods. By used of macro-meso unit cell finite element and control volume via introducing homogenization theory establish the relationship equation model between fabric structure and multi-scale flow under fabric deformation conditions，to clarify the permeability law of porous media physical properties and multi-scale pore structure and flow channel in deformation fabrics. This project aims to reveal the interaction mechanism and law of multi-scale flow impregnation and fibrous fabric assembly structure under fabric deformation in LCM process, which will offer a strong theoretical basis and scientific methods for liquid composite molding process and high performance and interface control of composites.

复合材料液体模塑成型（LCM）中织物的渗透率是非常重要的参数，但织物变形导致织物原本的内部结构、适形性、微孔结构等发生变化，从而引起织物局部渗透性的变化，最终将影响树脂渗透过程及制品的质量。本项目中，利用纤维运动学方法与织物变形表征手段，研究LCM过程中织物及预型件的多因素变形机制；采用宏观-细观多尺度分析方法，结合织物铺敷适形性及纤维运动学，探究LCM中织物变形时织物结构及多尺度微孔演变规律；借助于均匀化理论，运用宏观-细观晶胞有限元及控制体积法相结合的方法，建立织物变形条件下织物结构与多尺度流动方程模型，阐明变形作用时织物内部结构及多尺度渗透特性的交互作用机理。本项目旨在揭示LCM中织物变形时纤维织物集合体结构与多尺度渗透相互作用规律，为复合材料成型加工和复合材料的高性能化及界面调控等奠定理论基础和科学方法。

复合材料液体模塑成型（LCM）中织物的渗透率是非常重要的参数，但织物变形导致织物原本的内部结构、适形性、微孔结构等发生变化，从而引起织物局部渗透性的变化，最终将影响树脂渗透过程及制品的质量。该项目按照预期计划实施，优化技术路线和实验方案，构建理论方法，重点进行了织物及LCM成型加工时的变形特性与变形机理研究，探究了变形作用下纤维集合体结构刚度预测及变形适形性演变规律，并进一步分析了变形作用对织物结构及渗透性的影响关系，研究了织物细观模型及渗透性表征方法，构建了织物变形及多尺度渗透交互机理构效关系，实现了不同变形作用机制与交互渗透流动行为模拟等。取得了相关复合材料成型加工的关键技术和方法，并为高性能热固性复合材料制备提供了理论指导，拓展了风力发电、汽车等领域的深入拓展应用。项目成果揭示了LCM中织物变形时纤维织物集合体结构与多尺度渗透相互作用规律，为复合材料成型加工和复合材料的高性能化及界面调控等奠定了理论基础和科学方法。