▎ 摘　　要

NOVELTY - Preparing a graphene-toughened silicon carbide ceramic composite material involves adding graphene to the aqueous solution of alcohol and mixing evenly, and carrying out ultrasonic dispersion for 0.5-5 hours. The graphene dispersion liquid 0.5-5g/l is prepared. The ratio of ethyl orthosilicate and graphite oxide is 20:1-1:1. The tetraethyl orthosilicate is added to the graphite oxide solution, and then reducing agent is added, then magnetic stirring for 0.5-5 hours to obtain an oxidized graphite/ethyl orthosilicate mixed solution. USE - Method for preparing a graphene-toughened silicon carbide ceramic composite material (claimed). ADVANTAGE - The method enables to prepare graphene-toughened silicon carbide ceramic composite material with high machine performance and heat resistance. DETAILED DESCRIPTION - Preparing a graphene-toughened silicon carbide ceramic composite material involves adding graphene to the aqueous solution of alcohol and mixing evenly, and carrying out ultrasonic dispersion for 0.5-5 hours. The graphene dispersion liquid 0.5-5g/l is prepared. The ratio of ethyl orthosilicate and graphite oxide is 20:1-1:1. The tetraethyl orthosilicate is added to the graphite oxide solution, and then reducing agent is added, then magnetic stirring for 0.5-5 hours to obtain an oxidized graphite/ethyl orthosilicate mixed solution. The obtained solution is placed in a stainless steel reaction kettle and then heating to 100-200 degrees C for 1-24 hours, and filtering the product. The obtained product is washed with deionized water and absolute alcohol, and then dried in vacuum for 12-72 hours at 50-100 degrees C to obtain modified graphene/silicon oxide powder. The silicon carbide particles, additives, aluminum powder, and modified graphene/silicon oxide powder are added into the ball mill and mixed evenly fro 5-50 hours, and then passed through 200-2000 mesh sieve at 20-200MPa pressure. The obtained product is placed n a sintering furnace under argon for vacuum sintering at 1100-2100 degrees C for 0.5-5 hours, and then cooled to room temperature to obtain a graphene-toughened silicon carbide ceramic material.