| Over the past century,with the continuous advancement of technology and the continuous development of the machinery industry,aluminum-based composite materials have been widely used in aviation,aerospace and automotive because of their advantages such as high strength,high wear resistance,low density,and low thermal expansion coefficient.Industry and shipbuilding.Graphene is a new type of material with excellent performance,and it is also one of the materials with high strength,high modulus,and high thermal conductivity in the world today.If the aluminum-based composite material is combined with graphene and a small amount of silicon,copper,magnesium,and other elements are added,a new type of high-performance metal-based composite material,that is,graphene /aluminum-silicon based composite material will be obtained.However,due to the fact that few people have studied the performance of graphene / aluminum-silicon based composites at home and abroad,it has not been widely used in the field of machinery industry.Graphene / Al-15Si-4Cu-Mg is a composite material prepared in this experiment.The microstructure of the graphene / Al-15Si-4Cu-Mg composite was observed in a metallographic microscope.The observation results show that the proper addition of graphene can refine the silicon particles in the composite material to different degrees,making it more uniformly distributed in the aluminum matrix.Using a Brinell hardness tester,the microhardness of the graphene / Al-15Si-4Cu-Mg composite was tested.The test result is that as the content of graphene in the composite increases,the hardness value of the graphene / Al-15Si-4Cu-Mg composite material also increases;by graphene / Al-15Si-4Cu-Mg composite The test of some mechanical properties of the material,the experimental results show that the tensile strength and yield strength of the composite material increase with the increase of the content of graphene in the composite material.In the reciprocating friction and wear test,the friction curve images generated by Al-15Si-4Cu-Mg composite materials with different graphene contents were analyzed using a reciprocating friction and wear tester.Observation of the friction curve shows that as the graphene content in the composite increases from 0.3% to 0.7%,the maximum friction coefficient of the composite decreases from 0.9 to 0.65,and the fluctuation amplitude of the friction coefficient decreases from 0.72 to 0.48.It shows that the composites containing 0.7% graphene tend to be more stable during the friction and wear experiments.By observing the scanning electron micrograph of the composite material wear scar,the wear mechanism of the composite material is abrasive wear and adhesive wear.The scanning electron microscope conclusions show that adding a certain amount of graphene to the composite material can improve the ability of the composite material matrix to resist wear.In material cutting experiments,when the amount of graphene added in the composite increased from 0.3% to 0.7%,the maximum cutting force increased from1103 N to 1305 N and then decreased to 1106 N.The maximum The cutting force first increases and then decreases.When the spindle speed n increases from 4000 r / min to8000 r / min,the maximum cutting force decreases from 1197 N to 1007 N.When the feed per tooth increases from 0.05 to 0.15,the maximum cutting force increases from1100 N to 1250 N.When the cutting depth is increased from 0.2 to 0.6,the maximum cutting force is increased from 1000 N to 1150 N.In the graphene / Al-15Si-4Cu-Mg composite material cutting simulation process,the ABAQUS finite element software was used to establish a cutting simulation processing model,and the changes in mises stress during the simulation cutting process were analyzed.The simulation conclusion is that the mises stress reaches the maximum when the tool is just in contact with the workpiece;as the cutting progresses and is about to end,the mises stress gradually decreases. |
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