| Traditional metal matrix composites(MMCs)can effectively improve the wear resistance of materials,However,under the condition of impact abrasive wear,the advantages of MMCs cannot be fully exerted.Predecessors studied the three-dimensional network interpenetrating space structure composites with different volume fractions in the composite area through the configuration design of MMCs,and obtained that the composite area with the 50%volume fraction composites has the lowest wear rate,which is more pure than 40Cr pure matrix the wear performance is improved by 21.1%,which is 78.5%higher than that of the ZTAp uniformly distributed composite material.At the same time,the research group has studied the effect of the volume fraction of the composite zone,the heat treatment method and the presence or absence of abrasive on the impact abrasive wear performance of the composite,but it is not very comprehensive,there are also some important influencing factors such as the type of matrix in the composite zone,the size of the reinforcement and the impact energy that have not been studied.In order to further improve the impact abrasive wear performance of the structured composites,In this paper,a combination method of 3D printing and squeeze casting is used to successfully prepare a ZTAp reinforced three-dimensional network interpenetrating space structure composite material with a composite area accounting for 50%of the entire composite material volume,referred to as a configuration composites.Therefore,this paper further studies the effect of matrix type of composite zone,impact energy and reinforcement size on the impact abrasive wear performance of the configuration composites.Mainly through the hardness analysis,metallographic structure observation,XRD structure analysis,volume wear rate analysis,scanning morphology analysis and other detection methods to characterize its wear resistance in detail,discuss and analyze the wear mechanism of configuration composites.When the matrix region is 40Cr material,by adding Cr content on the basis of the composite region matrix 40Cr,the effect of the matrix in the composite region on the impact abrasive wear performance of the configuration composites was studied.The study found that with the increase of Cr content in the matrix of the composite zone(2%,5%and 15%),the carbide will gradually become more and thinner,which improves the solidity of the alloying elements in the matrix,after quenching and low temperature tempering,the structure is mainly composed of lath martensite.The hardness of the matrix in the composite zone is 462.1 HV,543.8 HV and 883.7 HV,respectively,and the volumetric wear rates of the samples are8.02?10-4cm3/min,5.31?10-4cm3/min and 5.46?10-4cm3/min,respectively.As the hardness of the matrix in the composite zone increases,the wear resistance of the composite material decreases first and then increases.It is not that the higher the hardness of the composite zone,the better the wear resistance of the material,because when the hardness of the material is too high,brittle fracture occurs,which makes the material wear seriously;When the hardness is moderate,during the wear process,the protruding ZTA particles will bear the main load to protect the matrix,and the surrounding matrix will also support and absorb energy for the ZTA particles at this time,the two complement each other,and at the same time The height of the composite area is also higher than that of the matrix area.The composite area will also play a role in resisting impact on the matrix area,and the matrix area will also play a role in supporting and absorbing energy in the composite area,so that the matrix area and the composite area also will complement each other,promote synergies,and jointly improve the wear resistance of the material.For the composite material with 40Cr material in the matrix zone and 5%Cr content in the composite zone matrix,the effect of the reinforcement particle size on the impact abrasive wear performance of the configuration composites was studied.When the reinforcement is 150 mesh ZTAp,the hardness of the composite zone is HBW 580.5,the matrix zone is HBW 520.4,the volume wear rate is 4.92?10-4cm3/min.When the reinforcement is 100 mesh ZTAp,the hardness in the composite zone is HBW 550.3,the matrix zone is HBW 510.2,and the volume wear rate is 5.31?10-4 cm3/min.The configuration composite material reinforced by 150 mesh ZTAp is 7.34%higher than the composite material reinforced by 100 mesh ZTAp,because the number of reinforcements in the composite area per unit area increases,the reinforcements can hinder the propagation and communication of cracks,and coarse particles break more seriously than fine particles,so the wear resistance of composites reinforced by fine particles is better than the composite material reinforced by coarse particles.The wear mechanism is mainly the embedding of the abrasive,the fragmentation of the particles and the shedding of the material.The effect of impact energy on the wear resistance of the material was studied.The material of the matrix area is 40Cr,and the composite material of the composite area has a Cr content of5%.The volume wear rate under the impact energy of 1.5J and 3.5 J is 5.31?10-4cm3/min and5.29?10-4cm3/min.Under the impact energy of 1.5 J,the ceramic particles are less broken,and the wear is mainly based on the ploughing and cutting of the substrate by the abrasive,under the impact energy of 3.5 J,the ceramic particles are broken more,and due to the configuration,the toughness of the composite material is improved,thereby improving the wear resistance of the material,The wear is mainly caused by particle crushing,embedment of abrasives,abrasive debris and exfoliation pits.The volume wear rate of pure matrix 40Cr material under 1.5 J and3.5 J impact energy is 3.97?10-4cm3/min and 4.82?10-4cm3/min,respectively,the wear mechanisms are mainly cracks,furrows,strain fatigue,pressed abrasives and metal cutting.The volume wear rate of high manganese steel matrix under 1.5 J and 3.5 J impact energy is7.57?10-4cm3/min and 4.71?10-4cm3/min,respectively,because high manganese steel undergoes severe plastic deformation under high impact energy,plastic deformation leads to an increase in work hardening and improves the strength and toughness of the material,so its wear resistance is better than that under low impact energy,and its wear failure mechanism mainly the embedding,cutting and furrowing of abrasives. |
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