▎ 摘　　要

NOVELTY - Preparation of carbon fiber composite, involves boiling carbon fibers in concentrated nitric acid and coating an epoxy sizing agent on the surface of carbon fibers, heating and reacting phenol, formaldehyde, and zinc oxide, dehydrating, adjusting the viscosity using methanol, cooling to obtain a phenolic resin, dispersing graphene in the phenolic resin, adding 2% oxalic acid as catalyst with respect to the total mass of phenolic resin, heating to 100 degrees C, reacting for 2 hours, heating and dehydrating at 170 degrees C or less to obtain graphene-modified phenolic resin, cooling and crushing, mixing the graphene-modified phenolic resin, carbon fiber, hexamethylenetetramine, wollastonite, carbon black, and calcium hydroxide, drying in an oven, plasticizing in an open mill, cooling to room temperature, crushing, hot-pressing, post-treating in an oven, cooling naturally in the oven, and taking out when the temperature is less than 60 degrees C. USE - Preparation of carbon fiber composite for pistons. ADVANTAGE - The method provides economical carbon fiber composites, which have low density, and small specific gravity and friction coefficient, and reduce noise generation during engine work, and reduce ionization consumption. DETAILED DESCRIPTION - Preparation of carbon fiber composite, involves boiling carbon fibers in 65% concentrated nitric acid and coating an epoxy sizing agent on the surface of carbon fibers, adding phenol, formaldehyde, and zinc oxide in a mass ratio of 50:50:1 to a four-mouthed bottle containing condensed water, heating and reacting at 80 degrees C for 2 hours, dehydrating to a water content of less than 5% under vacuum, adjusting the viscosity using methanol, cooling to 40 degrees C or less to obtain a phenolic resin, dispersing graphene in the phenolic resin in a mass ratio of 2:3, adding to a four-mouthed bottle containing a condenser, adding 2% oxalic acid as catalyst with respect to the total mass of phenolic resin, heating to 100 degrees C, reacting for 2 hours, heating and dehydrating at 170 degrees C or less to obtain graphene-modified phenolic resin, cooling and crushing, mixing 30 wt.% graphene-modified phenolic resin, 3 wt.% carbon fiber, 4 wt.% hexamethylenetetramine, wollastonite, 2 wt.% carbon black, and 1 wt.% calcium hydroxide for 20 minutes, drying in an oven for 120 minutes at 60 degrees C, plasticizing in an open mill at a front roller temperature of 70 degrees C and a rear roller temperature of 90 degrees C for 5 minutes, cooling to room temperature, crushing, hot-pressing at 30 MPa and 160 degrees C for 40 seconds, post-treating in an oven at 150 degrees C for 1 hour, cooling naturally in the oven, and taking out when the temperature is less than 60 degrees C.