▎ 摘　　要

NOVELTY - Production of graphene-reinforced titanium alloy rod involves casting titanium alloy composition, heat-treating obtained ingot, cooling, coating ingot surface with boron nitride, forging, subjecting rod to solution treatment, water-quenching, heating water-quenched rod, cooling, washing, drying, immersing resultant titanium alloy rod in an alkaline melt, pickling using pickling solution containing concentrated sulfuric acid, forming graphene film on the surface of rod, spraying coating containing titanium powder, silver metal and magnesium oxide powder, heat-treating, and cooling. USE - Production of graphene-reinforced titanium alloy rod used as substitute material for repairing hard tissue e.g. bones, joints and artificial tooth roots. ADVANTAGE - The method enabled production of graphene-reinforced titanium alloy rod with excellent mechanical property. DETAILED DESCRIPTION - Production of graphene-reinforced titanium alloy rod involves adding alloy composition to a high-vacuum arc melting furnace, stirring, casting into ingot, heat-treating ingot in a vacuum furnace by heating at 200-250 degrees C/hour to 920-940 degrees C for 6-10 hours under argon gas protection atmosphere, cooling at rate of 120-150 degrees C/hour to 550-580 degrees C for 2-6 hours, 80-90 degrees C/hour to 280-320 degrees C for 2-5 hours, and 50-65 degrees C/hour to 180-190 degrees C for 2-5 hours, respectively, further cooling the furnace to room temperature, coating ingot surface with boron nitride to prevent oxidation during processing at high temperature, forging at 900-1000 degrees C for 1-2 hours, grinding ingot surface defects, cooling forged ingot to room temperature, heating to 700-740 degrees C, stretching with pass deformation of 15-30% and cumulative total amount of deformation of 55-110%, subjecting obtained rod to solution treatment at 860-900 degrees C for 15-45 minutes in a box-type resistance furnace, water-quenching, heating water-quenched rod at 450-480 degrees C for 2-3 hours in argon gas protection atmosphere, cooling furnace to 280-310 degrees C for 3-4 hours and 180-220 degrees C for 5-6 hours, respectively, further cooling with water, washing heat-treated titanium alloy rod with 90-100 degrees C hot water, further washing with cold water to room temperature, drying titanium alloy rod with compressed air, blowing quartz sand to remove machining marks and increase roughness, immersing resultant titanium alloy rod in an alkaline melt at 350-550 degrees C for 30-60 minutes, pickling the surface of the rod by immersing in pickling solution at 40-50 degrees C for 15-45 minutes, immersing resultant rod in a solution containing 150-200 g/l sodium nitrate and 15-45 g/l sodium fluoride at 90-150 degrees C for 15-20 minutes, ultrasonically processing titanium alloy rod with isopropanol and ultrapure water, respectively, placing resultant rod in piranha solution for 30-60 degrees C, cleaning obtained hydroxylated titanium alloy rod with deionized water, placing cleaned rod in aminosilane solution, ultrasonically dispersing graphene oxide powder in distilled water, obtaining colloidal graphene oxide with concentration of 0.1-6 mg/ml, immersing resultant titanium alloy rod in colloidal graphene oxide at constant temperature, immersing resultant rod in mixed solution of hydrohalic acid and phosphoric acid, heating, washing resultant rod with deionized water until neutral, drying, obtaining titanium rod having graphene film on surface, spraying coating containing 60-80 pts. wt. titanium powder, 0.1-1 pts. wt. silver metal, 15-20 pts. wt. wollastonite powder, 0.1-0.5 pt. wt. silver oxide, 2-4 pts. wt. titanium diboride powder and 4-8 pts. wt. magnesium oxide powder, on titanium alloy rod by atmospheric plasma spraying process with argon gas flow rate of 15-30 l/minute, hydrogen flow rate of 15-20 l/minute, spray distance of 40-60 mm, powder feed rate of 5-10 g/minute and spraying current of 450-600 A to coating thickness of 0.5-3 mm, heat-treating at 550-650 degrees C for 1-2 hours, cooling to 150-200 degrees C for 24-48 hours, and further cooling to room temperature. The alloy composition comprises 7-10 %mass zirconium, 1.5-2.5 %mass iron, 0.5-0.8 %mass chromium, 0.5-0.9 %mass gallium, 0.25-0.75 %mass tin, 0.02-0.07 %mass hafnium, 1-2 %mass tantalum, 1-2 %mass aluminum, 0.25-0.45 %mass vanadium, 0.1-0.18 %mass boron, 0.12-0.18 %mass cerium, 4-15 %mass niobium, 9-13 %mass molybdenum, 0.001-0.005 %mass silver and remainder of titanium. The alkaline melt comprises 70-80 wt.% sodium hydroxide and 20-30 wt.% sodium nitrate. The pickling solution comprises 20-30 pts. wt. 98% concentrated sulfuric acid, 6-8 pts. wt. 36.5% hydrochloric acid, 1-2 pts. wt. alkyl imidazoline, 1-3 pts. wt. ethylenediamine and 30-60 pts. wt. water.