▎ 摘　　要

NOVELTY - Preparing graphene-loaded copper-reinforced copper-based high thermal conductivity composite material involves: (1) weighing multilayer graphene nanosheets and copper metal powder; (2) ball milling copper metal powder and grinding aid to obtain a sheet-shaped copper metal powder; (3) depositing copper atoms on a surface of multilayer graphene nanosheets to obtain copper-loaded graphene; (4) preparing polyvinyl alcohol aqueous solution, adding the sheet-shaped copper metal powder, stirring, heat-preserving to obtain hydroxylated copper flakes, and preparing dispersed graphene by using copper-loaded graphene; (5) adding hydroxylated copper flakes and dispersed graphene to containers, and ultrasonically vibrating to obtain a mixed layered material; (6) drying the obtained mixed layered material; and (7) adding the obtained graphene-copper mixed powder to a graphite mold, pressurizing, sintering, cooling, and then demolding. USE - The method is useful for preparing graphene-loaded copper-reinforced copper-based high thermal conductivity composite material used in aerospace, aviation, and electronic device. ADVANTAGE - The method provides graphene-loaded copper-reinforced copper-based high thermal conductivity composite material, which has excellent mechanical property and performs self-assembly and adsorption under ultrasonic vibration, and solves the problem of uneven graphene dispersion in the current graphene-reinforced copper-based composite material. DETAILED DESCRIPTION - Preparing graphene-loaded copper-reinforced copper-based high thermal conductivity composite material involves: (1) weighing 0.3-5 %mass multilayer graphene nanosheets and 95-99.7 %mass copper metal powder with a particle size of 1-15 microm; (2) adding the copper metal powder and a grinding aid to a ball mill tank according to the ball-to-material ratio of (2-20):1, and ball milling at 100-400 rpm for 2-15 hours to obtain a sheet-shaped copper metal powder with a planar size of 30-70 microm and a thickness of 100-300 nm; (3) depositing copper atoms on the surface of multilayer graphene nanosheets by plasma physical vapor deposition while stirring to obtain copper-loaded graphene whose copper loading amount of is 3-6%; (4) dissolving polyvinyl alcohol in water at 50-90degrees Celsius to a polyvinyl alcohol aqueous solution, adding the sheet-shaped copper metal powder, evenly stirring, heat-preserving in a water bath at 80degrees Celsius for 1-15 hours to obtain hydroxylated copper flakes, adding the copper-loaded graphene to 3-5% stannous chloride solution, ultrasonically processing for 10-100 minutes, then transferring to 3-5% palladium(II) chloride solution, ultrasonically processing for 10-100 minutes, rinsing with deionized water, and ultrasonically dispersing in absolute ethanol to obtain processed graphene nanosheets, adding to deionized water with 5 %mass sodium edetate, and ultrasonically dispersing to obtain dispersed graphene; (5) adding the hydroxylated copper flakes and the dispersed graphene to two containers respectively, ultrasonically vibrating, setting a switch at the opening of the container to control the switch to be turned on every 5-30 seconds, so that the dispersed graphene pass through a pipeline, then depositing and precipitating autonomously under the action of gravity in other container, leaving still for 4-8 hours to form a layered structure of graphene copper to obtain a mixed layered material; (6) drying the obtained mixed layered material in a drying oven at 60-90degrees Celsius to obtain graphene-copper mixed powder; and (7) adding the graphene-copper mixed powder to a graphite mold, placing on a press table together with the mold, pressurizing the mixed powder at 2-10 MPa and a pressure speed of 0.1-30 mm/minute and maintaining the pressure for 3-20 minutes, transferring the pre-pressed mixture together with the mold to a plasma sintering furnace, heating the furnace from room temperature to 800-1070degrees Celsius within 10-60 minutes under a protective atmosphere, sintering at 800-1070degrees Celsius for 2-30 minutes, cooling along with the furnace, and then demolding.