▎ 摘　　要

NOVELTY - Preparing graphene reinforced magnesium based composite material by injection molding involves using graphene, magnesium alloy, anhydrous ethanol, magnesium oxide and argon gas as chemical substance material in a measurement unit of grams, milliliters and cubic centimeters. The method involves weighing 30 plus minus 0.001g graphene and 5000 plus minus 0.001g magnesium alloy, and mixing it in mixing machine at a speed of 20 revolutions per minute for 30 minutes to obtain magnesium alloy graphene mixed particle. The injection molding machine barrel is preheated and has a total of H1, H2, H3, H4, H5, H6, NH and LNH areas, where H1-H4 area is a heating section in which H1 heating temperature is 480 degrees C, H2 heating temperature is 585 degrees C, H3 heating temperature is 600 degrees C and H4 heating temperature is 628 degrees C. The mixed particles are heated in H1-H4 region, H5 and H6 regions are heat-insulating regions, and temperature is set to 628 degrees C, and the formed slurry is heated for heat preservation. USE - Method for preparing graphene reinforced magnesium based composite material by injection molding. ADVANTAGE - The method enables to prepare graphene reinforced magnesium based composite material by injection molding, which uses device having advanced technology, accurate in data and compact in process, has a hardness of 82.2HV, tensile strength of 235MPa and elongation of 7.22%. DETAILED DESCRIPTION - The NH and LNH area are injection preparation zones, and has a temperature of 600 degrees C. The method involves feeding argon gas into injection molding equipment through input valve, passage time is 20 minutes, argon gas is filled into interior of the injection molding equipment, and input valve is closed. The mixed magnesium alloy graphene mixed particles are added to the molding machine storage hopper, and feeding screw in storage hopper continuously feeds the mixed particles into rotary shearing mechanism by rotating, where feeding amount is 800g each time and when it reaches the set amount then feed screw stops rotating. The number of revolutions of spiral shearing conveying rod inside barrel of feeding molding machine is set to 168 revolutions per minute, and spiral shearing conveying rod applies cutting shear force to mixed particles during the rotation process, which simultaneously conveys the slurry to inner side of front end cavity. The injection molding is carried out by using a heating machine to preheat forming mold at a temperature of 300 degrees C, and spraying the release agent magnesium oxide uniformly on surface of the mold cavity up to a thickness of 0.15mm. The semi-solid slurry is conveyed by screw to cavity in front of the punch, and when volume of slurry reaches 459cm3 then injection machine pushes the punch and shoots the slurry at a high speed of 3m/seconds, slurry is filled into mold cavity, a pressure of 200Mpa is applied, and then semi-solid slurry is solidified. The demolding is carried out by opening molding die, take out casting, and cooling it to 25 degrees C to obtain a graphene reinforced magnesium matrix composite. The obtained composite is cleaned with anhydrous ethanol, and dried to make the surface clean. The morphology, color, metallographic structure and mechanical properties of prepared matrix composite is detected, analyzed and characterized. The metallographic analysis is performed by using a metallographic analyzer. The morphological analysis is performed by scanning electron microscopy. The phase identification analysis is carried out by X-ray diffractometer, and hardness analysis is carried out by using a Vickers hardness tester. The tensile strength analysis is performed by using a microcomputer controlled electronic universal testing machine. The graphene reinforced magnesium matrix composite is a rectangular block. The hardness of graphene reinforced magnesium matrix composite is 82.2HV, tensile strength is 235Mpa, elongation is 7.22%, and graphene is uniformly dispersed in the magnesium alloy matrix to obtain matrix with good interface.