Research On Microstructure And Mechanical Properties Of Looped Fabric Composites

Woven composites, with good mechanical properties and excellent nccopy ability, it was rapidlyintroduced into general use in the field of aviation and astronautics. Looped fabric composites are anew type of woven composites. it can improve the performance of against delamination and impact byforming reinforced circles in the direction of Z on the fabric which can combine effectively with resinbetween two prepregs.This paper takes the coarse looped fabric composites as example, studies the micro-geometrystructure and mechanical properties of looped fabric composites and has three main aspects in thefollowing.The first part of this thesis focuses on investigations of the micro-geometry structure andin-plane mechanical properties of looped fabric composites. A mesoscopic mechanics model isestablished through reasonable assumption, then the fiber volume fraction is calculated. According toTsai-Wu tensor theory, averaging calculating method is used to analyze the tensile and compressivestrength of the looped fabric composites which is compared with the results of experiment.In the second part of this thesis the mechanical behavior of looped fabric composites is carriedout by the finite element method. A flatwise tension finite element analysis model of the loopedfabric composites is established. It is simulated using the FEA software. Flatwise tension strengthwhich is compared with the results of experiment are obtained by the analysis of damage evolutionprocess.The last part of this thesis performs the experimental research on the manufacturing process andmechanical properties. Experimental samples for meeting the requirements are made by the method ofvacuum glue process. The experimental research on tensile, compressive, in-plane shear, short-beamshear, flatwise tension and double lap shear properties is made. By compared with the mechanicalproperties of2D woven laminated composites, some beneficial conclusions are obtained.