Research On The Interface Characterization Performance And Mechanism Of Carbon/Carbon Composites Modified By Graphene

Carbon/Carbon composites are commonly used in aircraft and aerospacecomponents, because of their excellent mechanical properties at high temperatures.Their performance is known to depend functional groups of the carbon fibers and thematrix on the type of carbon fibers, matrix precursors, interface structure. In particular,the mechanical properties of bonding between fiber and matrix (fiber–matrix interface)Carbon/Carbon composites are very sensitive to the bondand processing conditions.For carbon/carbon composites, it has been shown that good mechanical propertiesdepend tremendously on load transfers at Fiber/Matrix interface. In C/C composites,too weak an interface may impair composite integrity, whereas too strong a bond mayinduce damage to fibres during heat treatment and brittle fracture behaviour. So, themodification of interface characteristics is essential for the development of C/Ccomposites with desirable and predictable behavior.Different concentration of the solution (0.01,0.05,0.1,0.5mg/ml) graphene wereintroduced by dipping the during the prepreg formation. The graphene-reinforced C/Ccomposites were characterized for effect of graphene concentration on microstructure,density, porosity, interlaminar shear strength (ILSS) and the damping behavior offibre/matrix interfaces. The increase in degree of graphitization was attributed tographeme filling the interface generated after carbonization which led to an increase inorientation and density. At0.05mg/ml graphene modified C/C composites, the highestILSS observed was10.5MPa (increased by25.5%), and the Shear strength offibre/matrix interface revealed an average increase (increased to19.1%). With theincreasing content of graphene, the fibre bundle/matrix interface strength of19%hasbeen improved, but when the concentration exceeds0.1mg/ml, the agglomeration ofgraphene started to appear and have negative effects on the integrated performance ofcarbon-carbon composites.In this thesis, we focus on the interface modification of Carbon/Carboncomposites by graphene coatings. Carbon/carbon composites with graphene attachedto the preform were produced.We want to establish the relationship between thestructure and performance through the characterization of interfacial properties of C/Ccomposites, in order to develop the theoretical basis for the process of composites.