▎ 摘　　要

NOVELTY - Graphene titanium matrix composite material strengthened by microalloying comprises titanium or titanium alloy as the matrix, and the microalloying metal is uniformly coated on the surface of the titanium or titanium alloy matrix in a quasi-continuous manner through physical bonding. The graphene is dispersed on the outer surface of the micro-alloyed titanium or titanium alloy substrate coated with metal, and forms a quasi-continuous network structure with in-situ titanium carbide (TiC) nanoparticles and intermetallic compound particles. The hardness of the metal for microalloying is less than the hardness of the titanium or titanium alloy matrix, and the ductility is greater than the ductility of the titanium or titanium alloy matrix. The yield strength and tensile strength of the graphene titanium matrix composite material strengthened by micro-alloying are higher than that of titanium matrix composite material prepared by corresponding titanium alloy powder of the same composition. USE - Graphene titanium matrix composite material. ADVANTAGE - The graphene titanium matrix composite material avoids the direct contact of graphene with the substrate, improves the distribution uniformity and structural integrity of graphene, and plays a synergistic strengthening role with TiC nanoparticles and intermetallic compound particles, and has strong maneuverability and is suitable for industrial production. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing a microalloyed graphene titanium matrix composite material, which involves: (A) selecting spherical titanium or titanium alloy powder as the matrix powder, and metal powder for microalloying is selected; (B) adding the matrix powder and the metal powder for microalloying to the ball mill, and then performing high-energy ball milling at high speed and low speed in turn, and obtaining titanium-based composite powder by sieving, and process parameters of the high-speed high-energy ball milling process comprises speed 450 revolutions/minute, ball milling time 30-50 minutes, ball-to-material ratio (2-3):1, and sphericity of the titanium-based composite powder is not less than 0.6, and the surface roughness Ra not greater than 2 micrometer; (C) dispersing graphene nanosheets in a solvent to obtain a suspension solution of graphene nanosheets; (D) adding titanium-based composite powder to the suspension solution of graphene nanosheets and mechanically stirring to obtain a mixed slurry paste, and process parameters of the mechanical stirring comprises speed 300-450 revolutions/minute, stirring time 2-4 hours, and heating temperature is 60 degrees C; (E) placing paste-like mixed slurry in a vacuum drying oven for drying treatment, and then screening to obtain a mixed powder coated with graphene; and (F) placing surface-coated graphene mixed powder in a spark plasma sintering machine for hot-press sintering to obtain a graphene titanium-based composite material that is microalloyed and synergistically strengthened.