Research On Mechanical Properties Of New Fabric Weaving And Composites Based On Structural Toughening

Fabric-reinforced resin-based composites have been widely used in various fields because of their excellent mechanical properties such as lightweight and high strength.However,the life of material is limited by delamination damage which occurred in composite interlayer due to external shocks,Inhibiting the delamination and improving the fracture toughness of the composites have become the focus of research in this field.Based on the idea of toughening between layers,a new kind of fabric-terry and plush fabric is designed and woven as reinforcement material.Terry and plush fabric reinforced composite material is a new kind of woven composite material,which uses the special structure-Z to the loop or plush on the surface of fabric.The toughened layer of the terry and plush is laminated to form a synergistic effect with the resin matrix in the middle layer,which can improve the interlaminar fracture toughness and the impact resistance of the composites.The main contents are as follows.A study on the compression properties of terry and plush fabric was carried out.It was found that the terry and plush fabric was compressed to form interlayer areas with interstices between layers due to the terry and plush on the fabric surface,The compressibility of the terry and plush fabric is inferior to the plain weave fabric,and finally the fiber volume content is reduced.The preparation of composite laminated plate through VARI process,and the basic mechanical properties of the composite plies were investigated,including tensile,compression,flexural and shear properties.The results show that the tensile strength,compressive strength and flexural strength of the composite laminates decrease with the decrease of the fiber volume content,while the shear strength does not decrease with the decrease of the fiber volume fraction.The shearing strength increases from 1.43%to 25.22%because of the combined action of the interlayer terry and plush structures and the resin.It can be seen that the terry and plush structure has a significant effect on the mechanical properties of interlayer.The fracture toughness and impact resistance of the composites were studied by the tests of mode I and mode II interlaminar fracture toughness and residual compressive strength after impact.The results show that the introduction of terry and plush structure can effectively improve the fracture toughness and load-carrying capacity of the laminate,and the pile structure is superior to the terry structure.No.8 plush fabric(plush is nylon)reinforced composite compared to non-toughened No.9 sample,G1c;increase of 87.07%,No.6 plush fabric(plush for the glass fiber)reinforced composite material,GⅡc increase of 34.62%.The Terry and plush structure can effective to improve the impact resistance of the composite such as No.4(terry fabric reinforced)increased by 26.70%for CAI and the CAI of sample No.5(plush fabric reinforced)increased by 28.89%.