▎ 摘　　要

NOVELTY - Preparation of nano-powder modified silicon carbide composite ceramic involves mixing raw silicon carbide powder, carbon powder, and nano-boron carbide powder or multi-layer graphene with deionized water, magnetically stirring, ultrasonically dispersing at room temperature, adding organic binder and dispersant to mixed slurry, ball-milling using zirconia balls in a ball milling tank, spray-granulating obtained wet-mixed slurry at 0.2-0.4 MPa, inlet temperature of 140-170℃ and outlet temperature of 60-110℃ to obtain powder with particle size of 90-240 µm, pre-pressing the powder with a tablet press at 15-20 MPa for 15-25 seconds, placing obtained ceramic blank in a graphite mold lined with a graphene paper layer, wrapping the mold with graphite felt, placing graphite indenters on both sides of the mold, placing the mold in a discharge plasma sintering furnace, applying pressure under nitrogen atmosphere, heating, sintering, heat-preserving, and cooling. USE - Preparation of nano-powder modified silicon carbide composite ceramic (claimed) used in energy industry, automobile industry and armor protection application. ADVANTAGE - The method uses the discharge plasma sintering technology, the preparation is fast, the technique is simple, it can obtain the complex phase ceramic with small and uniform crystal grain, high strength and toughness in a short time. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for the nano-powder modified silicon carbide composite ceramic, which is nano-powder modified silicon carbide-boron carbide composite ceramic comprising 78-93 %mass silicon carbide powder, 5-20 %mass nano-boron carbide powder and 2 %mass carbon powder, or nano-powder modified silicon carbide-graphene composite ceramic comprising 96-97.85 5 %mass silicon carbide powder, 0.15-2 %mass multilayer graphene and 2 %mass carbon powder.