Optimization Of Preparation Technology And Performance Of Aluminum-Magnesium-Graphene Composite Coating Under THF-C₆H₆-LiAlH₄-AlCl₃ System

Aluminum alloy has many advantages,such as its low density,good corrosion resistance and formability,high specific strength and low cost.It also has excellent process properties and good thermal and electrical properties.,Ship building,nuclear industry,etc.have broad application prospects.However,there are still some problems and disadvantages of aluminum alloys,such as low hardness and low corrosion resistance.At present,the main method used to solve these problems is to microalloy the alloy.Adding Zr,Sc,Zn,Mg and other elements to the aluminum alloy are good examples.In addition,after the nano-material is integrated into the alloy material,its inherent excellent function can perfectly match the alloy material,so that the hardness,tensile properties,surface roughness,anti-erosion ability of the alloy material can be improved,improve the original alloy coating on the lack of function.Taking this background as the starting point,this project attempts to add anhydrous Mg Cl₂ and graphene to the THF-C₆H₆-Li Al H₄-Al Cl₃ system,adopt organic electrodeposition,and use 7075 aluminum alloy as the substrate to optimize the conductivity of the basic plating solution.With the stability of the plating solution,the aluminum-magnesium-graphene composite coating with optimized mechanical properties is prepared,thereby improving the defects of the aluminum alloy.At the same time,orthogonal test and single factor experimental schemes were designed to analyze the influence of four process factors on the mechanical properties of the composite coatings,including graphene content,current density,rotor speed,and plating time.The coating is characterized.This topic draws the following conclusions:?1?The preparation process of the basic plating solution is as follows:firstly configure"a solution of lithium aluminum hydride in tetrahydrofuran"and mark it as"No.?";then configure"a solution of aluminum chloride and magnesium chloride in benzene-tetrahydrofuran"and mark it as"?"No.solution";add"No.? solution"into"No.? solution"and stir to obtain"basic plating solution".?2?The preparation process of the electroplating solution is as follows:"No.? solution"is added to"No.? solution"to make it fully mixed,and then graphene is added for electroplating.?3?It is obtained from orthogonal test that the order of the influence degree of the four process factors of graphene content,current density,plating time,and rotor speed on the Vickers hardness and friction coefficient of the aluminum-magnesium-graphene composite coating are:Graphene content>current density>plating time>rotor speed.The preferred process factors for preparing the composite coating are:a graphene content of 5.0g/L,a current density of 6A/dm2,a rotor speed of 250r/min,and a plating time of 45min.?4?After SEM,XRD,Laman and other inspection and analysis on the aluminum-magnesium-graphene composite coating,it was proved that graphene exists in the coating and lacks itself.It also characterizes the micro-morphology,elemental composition,and graphene-encapsulated morphology of the composite coating.?5?From the single-factor experiment,the best process factors for preparing the aluminum-magnesium-graphene composite coating are:graphene content of 5g/L,current density of 7A/dm2,rotor speed of 250r/min,and electroplating duration of 45min.