Micro-simulation Of Intralaminar Damage In Woven Carbon Fiber Reinforced Composite

In recent years,with the increasing demand,application and recognition of composite materials in industrial engineering,the research on fiber-reinforced composite materials is also concerned,mainly around its mechanical properties and damage mechanism.According to the material research experience,the research methods are mainly divided into experiment,theory and simulation.With the deepening of the research,there are still difficulties to be overcome,which are mainly divided into three points: accurate description of progressive damage mechanism of woven composite;Determination of appropriate damage prediction and loss effect model of woven composite;performance prediction of woven composite under various complex working conditions.Among them,the research on the progressive effect of in-plane shear deformation caused by the structural characteristics of woven fabric on the material performance is still insufficient under the complex load applied in practice.Therefore,in this paper,through the unidirectional tensile and in-plane shear tests and elastic research of woven composites,the expansion process of various damage modes of the test specimens is revealed.Based on the theory of finite element and progressive damage evolution,the material model is customized,and the macro-micro scale simulation is carried out.Compared with the test,the deformation of woven structures of woven composites under tensile and in-plane shear conditions is realized Analysis and prediction of the influence of mechanical property change and progressive damage failure.Firstly,the finite element model and theoretical model are established around the elastic stage of woven composites.The comparison results show that the two models can effectively predict the macro elastic properties of the material,in which the theoretical model calculation is convenient and fast,while the micro finite element method can clearly and accurately simulate the deformation and stress-strain distribution of woven composite under various loads.Secondly,based on the digital image correlation method,the unidirectional tensile test of the woven composite is carried out,and the distribution rule and damage process of the material strain field under the load are analyzed combined with the test phenomenon.The finite element software ABAQUS was used to simulate the macro drawing process of woven composites.Based on the three-dimensional Hashin failure criterion,the linear continuous stiffness degradation scheme is selected to simulate the damage evolution,and the VUMAT user subroutine is written to realize the micro prediction of the failure damage expansion process of materials,which verifies the effectiveness of the simulation.On this basis,the influence of changing process parameters on the failure performance of materials is studied.Finally,according to the standard test method,the in-plane shear test of the woven composite is carried out,and the macro in-plane shear model is established.Based on the above model,aiming at the in-plane shear load,the scheme of material stiffness reduction is optimized,the progressive damage model of the material is updated,and the prediction of the change of mechanical properties and damage process under the in-plane shear deformation of the material is realized,and the damage expansion of the material is analyzed The influence of braiding angle on failure performance is discussed.