Study On The Mechanical And Thermal Properties Of 3D Braided Composites With Graphene Nanoplatelets/Carbon Nanotubes Reinforced Resin Matrix

The application range and proportion of light weighted composites with high strength structure and function integration is one of the important indicators to evaluate the advancement of future aircraft.Graphene nanoplatelets(GNPs)and carbon nanotubes(CNTs)are widely used in the development of new multifunctional nano-resin composites as potential resin reinforcements due to their excellent mechanical-thermalelectrical-magnetic properties.3D braided composite materials are a typical structural form of textile composite material.It has good structural integrity,can overcome the fatal weakness that traditional laminated structures are easy to delaminate with excellent comprehensive mechanical properties.GNPs and CNTs will be used as nanoreinforcements in this study.3D braided composites with GNPs/CNTs reinforced resin matrix is a novel multi-level and multi-scale reinforced textile composites modified by nano fillers.It organically integrates nanocomposites and textile composites via the coupling effect and synergistic strengthening of cross-scale reinforcements.This is expected to realize the integrated design of material structure and function and improve the comprehensive performance.This is of great significance for promoting the development and engineering application of the new textile composites modified by nano fillers with integrated load-bearing ability and multi-functions.A multi-scale cell prediction model for mechanical-thermophysical properties of 3D braided composites with GNPs/CNTs reinforced resin matrix is proposed in this paper via a cross-scale modeling method.The main influencing factors of mechanical-thermal properties of materials and their changing rules were deeply studied in this research.Firstly,on the nano-scale,based on the random distributed configuration of GNPs/CNTs in the resin matrix,a finite element model of GNPs/CNTs modified resin matrix was established in this paper to explore the influence of the mass ratio of GNPs and CNTs on the mechanical-thermal properties of the matrix.Then,on the micro-scale,the GNPs/CNTs modified resin matrix was composite with carbon fiber.This paper predicts the equivalent mechanical-thermal properties of GNPs/CNTs modified yarn bundle with micromechanical methods.Finally,on the mesoscale,based on the finite element model of the inner cell of 3D four-directional braided composites in this paper.It explores the influence of fabric braiding process parameters and GNPs/CNTs mass ratio on the mechanical-thermal properties of 3D braided composites with GNPs/CNTs reinforced resin matrix.By comparing with the experimental data from the available validation,the rationality and effectiveness of the multi-stage and cross-scale analysis model for predicting the mechanical and thermal properties of typical 3D braided composites with GNPs/CNTs reinforced resin matrix were verified.Via the systematic discussion of the influence of important factors such as the content relationship between GNPs and CNTs and the braiding process parameters on the mechanical-thermal properties of materials,some valuable and important conclusions had been obtained.This paper preliminarily reveals the synergistic strengthening mechanism of the new materials,which lays a solid theoretical foundation for the optimal design and analysis of the multi-scale reinforced textile composites modified by nano fillers.