Modification of Longitudinal Modulus of 3D Full Five Directional Braided Composite Materials Base on Energy Theory  

作　　者：Apeng Dong Shu Li Wenguo Zhu Jing Pu 

机构地区：[1]School of Aeronautic Science and Engineering,Beihang University,Beijing 100191,China [2]Faculty of Engineering,University of Nottingham,Nottingham NG7 2RD,United Kingdom

出　　处：《Journal of Beijing Institute of Technology》2019年第3期651-658,共8页北京理工大学学报（英文版）

基　　金：Supported by the National High Technology Research and Development Program of China(2012AA112201)

摘　　要：The aim of this paper is to investigate the longitudinal modulus of three dimensional full five directional (3Df5d) braided composite. First, the analytical model of the internal unit cell is established based on its topological structure. Then, according to the intrinsic relation of different cells, the axial moduli of internal, surface and corner cells are systematically deduced, and the influence of corner-cell periodic discontinuity on the moduli is also analyzed. Finally, considering the actual shape of axial yarns after consolidation, the longitudinal moduli of the different cells are modified based on energy theory. The technology factor λ is also proposed in this modification. The results show that the axial mechanical properties of this material can be strongly designable. The straightness of the axial yarns greatly affects the longitudinal modulus. Technology factor λ is between 1 to 2, corresponding to the minimum and the maximum modulus, respectively.The aim of this paper is to investigate the longitudinal modulus of three dimensional full five directional(3 Df5 d) braided composite.First,the analytical model of the internal unit cell is established based on its topological structure.Then,according to the intrinsic relation of different cells,the axial moduli of internal,surface and corner cells are systematically deduced,and the influence of corner-cell periodic discontinuity on the moduli is also analyzed.Finally,considering the actual shape of axial yarns after consolidation,the longitudinal moduli of the different cells are modified based on energy theory.The technology factor λ is also proposed in this modification.The results showthat the axial mechanical properties of this material can be strongly designable.The straightness of the axial yarns greatly affects the longitudinal modulus.Technology factor λ is between 1 to 2,corresponding to the minimum and the maximum modulus,respectively.

关 键 词：braided composites BRAIDING parameters ELASTIC MODULUS strain energy technology factor 

分 类 号：TB33[一般工业技术—材料科学与工程]