Preparation And Friction And Wear Properties Of (SiCp+Gr)/6092Al Composite

Compared with single-reinforced aluminum-based composite materials,aluminum-based composite materials reinforced with different components and reinforced particles have excellent mechanical properties and friction and wear properties,and have been more and more widely used in aerospace and automotive fields.Copper alloys that are used as friction and wear parts can be replaced by aluminum,in older to save copper,and reduce the use of fuel to protect the environment.In the experiment,6092 aluminum alloy was used as the matrix,and aluminum matrix composites with spherical graphite particles?Gr?and SiCp?SiC particle?single-phase reinforcement and?SiCp+Gr?hybrid reinforcement were respe-ctively prepared by powder metallurgy to research their mechanical properties and friction and wear properties.To verify the idea that SiO₂ sol coated on the surface of Gr at high temperature sintering to generate SiC to hinder the contact between Gr and Al to form Al₄C₃,including the comparison of mechanical properties and corrosion properties.SEM was used to analyze the microstructure,tensile fracture,corrosion morphology and wear morphology of the composite.XRD was used to analyze the phase of the composite.The main research work is as follows:?1?The composite material and matrix were prepared by powder metallurgy,and the density of the composite material was calculated,and it was found that the density of the prepared material was more than 99%;by observing the OM image of the composite mate-rial,it was found that the reinforcement phase was perpendicular to the extrusion direction.The distribution is free of defects such as particle aggregation and pores,and the distribution of SiCp and Gr along the extrusion direction both exhibits a certain orientation.The tensile properties of the prepared materials were tested,and it was found that ?20%SiC+5%Gr?/6092Al reached the maximum tensile strength and yield strength,respecti-vely up to 474MPa and 400MPa,while ultra tensile strength and yield strength of 15%Gr/6092Al are the smallest,326MPa and 305MPa respectively.?2?Because of the interface reaction between Gr and Al during the preparation of composite materials,excessive Al₄C₃ will weaken the mechanical properties of the comp-osite material.In this paper,XRD is used to?10%SiCp+5%Gr?/6092Al and?10%SiCp +5%Gr?SiC??/6092Al did not observe Al₄C₃ in the phase analysis.The microscopic morphology and mechanical properties of the composite materials prepared by Gr?SiC?and Gr are analyzed,and it is found that the idea of coating SiO₂ sol on the surface of Gr is not feasible;through corrosion experiments,it is found that the corrosion of composite materials is more likely to the microporous defects between the substrates begin and undergo the proc-ess of pitting?intergranular corrosion.?3?15%Gr/6092Al,?10%SiCp+5%Gr?/6092Al and?20%SiCp+5%Gr?/6092Al under different loads?10N,15N and 20N?and different wear speed rate?0.5m/s,0.75m/s and 1m/s?was studied,and it was found that the addition of SiCp can enhance the hardness of the composite,and when the SiCp content increases,due to the wear of SiCp in the unit wear surface increase,bear more load,reduce the direct contact between the friction pair and the sample,make the hybrid reinforced composite material wear rate and friction coefficient more stable under different wear conditions,and 15%Gr/6092Al is under load When 20N wear rate is 1m/s,the test cannot be performed as required.?4?The factors that reduce the friction coefficient and wear rate of composite materials are combined through Taguchi,and the conditions for determining the minimum wear rate and friction coefficient are L=10N,S=0.75m/s,R=10%and L=10N,S=0.75m/s,R=0%;based on the analysis of variance,the factors affecting the wear rate and friction coeff-icient were sorted,and it was found that the SiCp volume percentage alone,the interaction of the SiCp volume percentage and the slip rate,and the slip rate alone had the most import-ant effect on the wear rate and friction coefficient impact.