Study On Mechanical Properties Of Carbon Fiber 2.5D Reinforced Woven Composites Based On Different Fineness

2.5D woven composites is a part of 3D woven composites.It is not hierachical.It has high strength,high stiffness,corrosion resistance;perfect mechanical properties of thickness direction as well as three-dimensional woven composites.2.5D woven composites is an important branch of three-dimensional woven composites,and it has excellent designability than three-dimensional composites.2.5D woven composites have been widely used in the aerospace,military,marine and automotive fields,so it has important significance to study the mechanical properties of 2.5D woven.The mechanical properties composites in their essence are decided by their reinforcements.The key factors affecting the properties of reinforcements are the structure of reinforcements,the design parameters and the raw materials.In this artical,based on the 2.5D layer-layer angle interlock structure,using the similar 2.5D fabric design method and reasonal design parameters,six 2.5D layer-layer angle interlocking woven fabric with difference fineness were woven.It is woven by the loom for weaving small sample.the six 2.5D carbon fiber preforms were synthesized with epoxy resin by RTM technology.The tensile,bending and compressive mechanical properties were measured by universal strength machine.The results showed thatThe change-of fiber fineness in the ordinary 2.5D angle interlocking structure affects the buckling state and bending degree of the warp in the preform fabric,and then affects the tensile properties of the material.The tensile properties are 12K>3K>6K.The change of the fineness of carbon fiber raw material affects the aggregation distribution of a certain number of fiber bundles.The more obvious the aggregation of carbon fiber bundles is,the more the aggregation situation will affect the generation of holes between the resin and the material.The bending performance is:3K>12K>6K in the vertical direction and in the weft direction is 3K>6K>12K.The compressive strength of compressive properties decreases with the fineness of fiber,and the effect of zonal compression is not obvious.Using the ABAQUS finite element analysis softwae,the finite element analysis of the tensile and bending was carried out by using the actual size model.By constrasting with the actual load-displacement curve,it was verified that the model constructed in this artical was reasonable for analysing the 2.5D layer-layer angle interlocking composites.