| Wear failure is one of the most common failure forms in the use of mechanical parts,especially in heavy equipment such as In iron and steel metallurgy,coal,mining.The joint action of impact and wear will always cause the failure of the jaw plate of the mining crusher and the lining plate of the grinding machine,so it is an urgent problem to improve the anti-wear ability of materials and the utilization rate of wear resistant alloy materials.The layered metal composite material used for the key wear-resistant parts of coal machine equipment can give full play to the performance strength of each component material,possessing the excellent characteristics of high strength,high toughness,high cost performance and high temperature resistance,corrosion resistance,impact resistance.Abrasion resistance is one of the key indexes of wear-resistant parts.Therefore,the development of high efficiency anti-wear composite material will be the great significance for reducing the probability of wear failure of coal mine machinery and improving the reliability,profitability and competitiveness of coal machinery equipment.It is difficult to combine wear resistance with mechanical properties of layered wear-resistant composite materials for coal engines.In this manuscript,BTW1 and Q345R were used to obtain wear-resistant steel composite plates with high wear resistance and good mechanical properties through rolling process.BTW1 is wear-resistant steel with good wear resistance.Q345R is carbon steel with good mechanical properties and low cost.On the basis of this research,a new process of corrugated roller rolling compound was proposed.A new process of corrugated roller rolling compound is used to obtain the wear-resistant steel BTW1/Q345R composite plate,which can enhance the bonding strength of heterogeneous metals and improve the warping of composite plate.This technique can not only improve the warping phenomenon by coordinating the deformation of heterogeneous metals,but also increased the bonding area of heterogeneous metals,enhanced the bonding strength of interface,and obtained the metallurgical bonding.Finally,wear-resisting steel composite board with excellent performance would be obtained.Specific research contents are as follows:(1)The thermal compression and deformation behavior of wear resistant steel BTW1 were studied by using the Gleeble3800 thermal mechanical,and the relationship between the activation energy of thermal deformation and the deformation mechanism under different deformation conditions was fully discussed.BTW1/Q345R composite hot compression deformation was processed according to thermal deformation properties of wear-resistant steel BTW1.Composite thermal compression constitutive relation model and hot working diagram were established.The relationship model of "composite process parameters-process window-organization evolution" of composite plate BTW1/Q345R compression deformation was obtained.The optimal matching relation of "composite process parameters-organization-performance" was established.The influence mechanism of compression thermal deformation was explored to provide theoretical guidance for subsequent composite rolling;(2)Based on the study of BTW1/Q345R composite thermal deformation behavior,the abrasion resistant steel BTW1/Q345R composite plate was prepared by rolling composite process.The microstructure differences and mechanical properties of rolled composite plates were analyzed and compared.When the cumulative composite deformation was 80%:at the BTW1/Q345R composite board bonding interface,the oxide film was completely broken.At this time,the interface was flat and elements were uniformly dispersed,and a 10 m thick metallurgical bonding layer was formed.Finally,the interface of BTW/Q345R composite board was strengthened and toughened.A series of mechanical properties tests showed that the tensile strength and yield strength of the composite plate under this process condition reached to 605MPa and 512MPa respectively,the elongation after fracture was 21.05%,and the bonding strength was 232MPa.The degree of coordinated deformation of bimetallic materials was better,which provided a theoretical basis for promoting the popularization and application of wear-resistant steel BTW1/Q345R composite board.(3)The wear-resistant steel BTW1/Q345R composite plate obtained from rolling was annealed before being put into use,and the influence mechanism of different annealing processes on the wear-resistant performance of the composite plate was explored.The effects of different annealing processes on the wear resistance of wear-resistant steel BTW1/Q345R composite board were explored.First,according to the austenite matrix of wear-resistant steel BTW1,different annealing processes were selected to treat the rolled composite plate.After the annealing treatment,the friction and wear results of the composite plate were compared and analyzed after the large load and long time friction and wear experiment.The results showed that the microstructure of composite plate was refined with the increase of annealing temperature.When the annealing temperature was 860?,the maximum scratch width of the cladding layer BTW1 was 1.419mm,and the maximum wear amount was 42.44×106 ?m3.The wear resistance of the cladding layer BTW1 was relatively the best.(4)There are still some problems in flat rolled composite plate,such as plate profile difference-warping,low bonding strength-cracking along interface.Based on the rolling compound research,a new rolling compound technology of corrugated roll was put forward.A step periodic load was applied to the rolled piece by the corrugated roller.The effects of different wavy periods on the interface microstructure and mechanical properties of BTW1/Q345R laminated composite plate were revealed.When the rolling temperature was 1200? and the reduction was 60%,the composite plate was rolled by the roll with 72 per circle corrugations and the wave depth was 1.5mm.The warping degree of composite board decreased by 50%,yield strength increased by 4.7%,tensile strength increased by 15.2%,elongation after fracture increased by 20.7%,and shear strength increased by 18%.This was mainly on account of the periodic local large stress exerted by the corrugated roller can promote the metal to reach the stress peak and yield limit and gradually diffuse to both ends,and increased the composite bimetal bonding area.It was beneficial to realize metallurgical bonding of materials and improve the comprehensive properties of composite plates to a greater extent. |
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