▎ 摘　　要

NOVELTY - Performing semi-solid casting molding method comprises using magnesium alloy ingot, graphene oxide, polyvinyl alcohol, deionized water, absolute ethanol, magnesium oxide release agent. The surface treatment of rod-shaped magnesium alloy particles are used to prepare mixed particles by cutting rod-shaped magnesium alloy particles. The metal particle cutting machine is used to chop 2500g magnesium alloy ingots into lengths of 5 plus minus 1.5mm and cross-sectional equivalent diameters of 0.50 plus minus 0.15mm rod-shaped magnesium alloy particles. USE - Method for performing semi-solid casting molding method for graphene oxide composite magnesium-based materials. ADVANTAGE - The method enables to perform semi-solid casting molding method for graphene oxide composite magnesium-based materials, which has advanced technology and accurate data. The prepared graphene oxide composite magnesium-based material castings have good internal structure compactness, no shrinkage holes, shrinkage defects, round and small crystal grains, and graphene oxide is uniformly dispersed in the matrix, has agglomeration, good interface bonding, casting tensile strength up to 295MPa, elongation rate up to 5.5%, hardness up to 103HV, and it is an advanced semi-solid casting molding method for graphene oxide composite magnesium-based materials. DETAILED DESCRIPTION - Performing semi-solid casting molding method for graphene oxide composite magnesium-based materials, comprises using magnesium alloy ingot, graphene oxide, polyvinyl alcohol, deionized water, absolute ethanol, magnesium oxide release agent. The surface treatment of rod-shaped magnesium alloy particles are used to prepare mixed particles by cutting rod-shaped magnesium alloy particles. The metal particle cutting machine is used to chop 2500g magnesium alloy ingots into lengths of 5 plus minus 1.5mm and cross-sectional equivalent diameters of 0.50 plus minus 0.15mm rod-shaped magnesium alloy particles. The amount of 20000mL deionized water is added to the polyvinyl alcohol solution box in the mixed particle preparation room, turned on and the first thermostat is adjusted in the PVA solution tank to keep the temperature of deionized water at 85 degrees C, then 600g of polyvinyl alcohol is added, heated for 0.5h. The amount of 20,000 mL of deionized water is added to the graphene oxide dispersion tank in the mixed particle preparation room, the third thermostat is turned on and adjusted in the graphene oxide dispersion tank to keep the temperature of deionized water at 50 degrees C. The stirring time is 40 minutes, and then the third ultrasonic vibrating table and the third thermostat are turned off to obtain the graphene oxide dispersion. The rod-shaped magnesium alloy particles and 18,000 mL of deionized water is added to the deionized water tank in the mixed particle preparation room. Then monorail crane and tongs are used to take the processing tank out of the polyvinyl alcohol solution tank and put it into the deionized water tank, so that all the rod-shaped magnesium alloy particles are immersed in deionized water. The second ultrasonic vibration table are turned under the deionized water tank for vibration cleaning for 15 minutes, and then the second ultrasonic vibration table and the second thermostat is turned off. Then the third ultrasonic vibrating table and the third thermostat is turned off, and let stand for 20 minutes. The rod-shaped magnesium alloy particles adsorbed with graphene oxide are put into a constant temperature oven for drying at 60 degrees C for 30min. The mixed particle block and magnesium alloy block are placed and 2500g magnesium alloy ingot is cut into magnesium alloy block with size 50x 50x 40mm. The mixed particle block and the magnesium alloy block are put into a preheating furnace for preheating at 220 degrees C for 25min. The protective gas cylinder is introduced into the semi-solid smelting furnace through the air inlet pipe on the semi-solid smelting furnace. The inflow speed of the protective gas is 200 cm3/min. The exhaust pipe on the semi-solid smelting furnace is used to control the air pressure in the furnace to keep the air pressure in the furnace at 1 atmosphere. The electromagnetic stirrer in the semi-solid melting furnace is turned on for rotating magnetic field stirring, the stirring frequency is 35Hz, clockwise stirring and counterclockwise stirring alternately. The ultrasonic frequency is 100kHz, the stirring time is 5min, then the fourth ultrasonic vibrating table is turned off, and it is allowed to stand at a constant temperature for 5min to prepare a semi-solid mixed slurry. The preheating molding mold adopts resistance wire heating method to preheat the movable mold core and the fixed mold core of the molding mold. The preheating temperature of the movable mold core is 330 degrees C, and preheating temperature is 350 degrees C. The magnesium oxide release agent is sprayed on the surface of the cavity of the forming mold with a spray thickness of 0.05mm. The semi-solid mixed slurry is injected into the cavity of the forming mold to turn on the electromagnetic pump, and the electromagnetic pump transports the semi-solid mixed slurry in the semi-solid melting crucible to the cavity of the forming mold through the material pipe. The flow rate of the electromagnetic pump is 300g/s, and the static head pressure is 0.55 plus minus 0.05MPa. After the semi-solid mixed slurry fills the cavity of the forming mold, the electromagnetic pump is continuously pressurized to increase the static head pressure for 25s, and then the electromagnetic pump is turned off to obtain the graphene oxide composite magnesium-based material casting. The graphene oxide composite magnesium-based material casting is demolded to open the forming mold, and the ejection mechanism of the forming mold ejects the graphene oxide composite magnesium-based material casting. The graphene oxide composite magnesium-based material casting is removed, placed it on a wooden plate, and cooled it to room temperature in the air. The steel wire brush is used to clean the parts and surroundings of the graphene oxide composite magnesium-based material castings, and then the graphene oxide composite magnesium-based material castings is cleaned with absolute ethanol, and then dried. The detection, analysis, and characterization of the morphology, structure and mechanical properties of the graphene oxide composite magnesium-based material casting is performed. The metallographic microscope for metallographic structure analysis, electronic universal testing machine is used for tensile strength and elongation analysis. The internal structure of the graphene oxide composite magnesium-based material casting is good, and there is no shrinkage cavity or porosity defect. The crystal grains are round and small, the graphene oxide is uniformly dispersed in the matrix without agglomeration, and the interface is well bonded. The tensile strength of the casting is 295MPa, the elongation is 5.5%, and the hardness is 103HV.