Preparation method for graphene-modified high thermal conductivity three-dimensional carbon/carbon composite material

The present invention discloses a preparation method for a graphene-modified high thermal conductivity three-dimensional carbon/carbon composite material. The preparation method comprises the steps of: using graphene oxide and PAN carbon cloth as raw materials, and forming a graphene oxide film on the surface of carbon fiber through an impregnation method; in a high-temperature hydrogen atmosphere, reducing the graphene oxide film into graphene; and then performing CVI densification and graphitization treatment to obtain the graphene-modified high thermal conductivity three-dimensional carbon/carbon composite material. The preparation method provided by the present invention is simple in process and convenient in operation, and can significantly improve thermal conductivity and bending strength of the three-dimensional carbon/carbon composite material, thereby achieving large-size and large-scale preparation of the three-dimensional carbon/carbon composite material. According to different using requirements, the preparation method for a graphene-modified high thermal conductivity three-dimensional carbon/carbon composite material can further adjust the types, contents and fiber spacing of z-directional puncture fibers so as to expand the using field of the three-dimensional carbon/carbon composite material. The three-dimensional carbon/carbon composite material has good market value and application prospects.