| In recent years,with the synchronous advancement of new industrialization and agricultural modernization,new performance requirements have been put forward for the materials used in industry.New industrial materials with high strength and difficult processing characteristics such as high temperature alloy,titanium alloy,ceramics,non-ferrous metals have been widely used,and higher requirements have been put forward for the processing tools.It has been estimated that tool wear costs the global economy hundreds of billions of dollars each year.It is an eternal topic in the field of tool research to improve the cutting performance,reduce tool wear and extend tool service life as much as possible.Due to its many advantages,cemented carbide plays an important role in the actual production and processing of tool materials.However,the traditional strengthening treatment methods of cemented carbides have certain defects in some aspects,while the electromagnetic field treatment technology,as one of the emerging advanced technology,is a green and pollution-free treatment technology,which can significantly improve the material properties and improve the material microstructure defects.This technology can improve the cutting performance of low-end tools,meet the machining requirements of hard-to-machine parts,and optimize the physical characteristics of high-end tools to extend their service life.Therefore,it is of great significance to explore the suitable strengthening processing parameters and processing technological parameters of cemented carbide for reducing production cost,ensuring product quality and improving productivity.In this paper,YT15 cemented carbide tool as the research object,using COMSOL software to simulate the processing process,get the macroscopic distribution of the working cavity electromagnetic field and the influence of electromagnetic field on the tool.Then,the cutting force,tool wear and tool service life of the tool were analyzed by the self-made pulsed electromagnetic equipment.The influence of magnetic field intensity,magnetic pulse group,electric field intensity and electric pulse group on the performance of the tool was studied.By analyzing the experimental results of cutting tool,the better pulsed electromagnetic field process parameters were selected.Based on the optimized processing parameters,the cutting process parameters of the tool were experimented.According to the experimental results,the empirical models of the main cutting force and the friction coefficient of the tool surface were established.Finally,the minimum main cutting force and tool surface friction coefficient were taken as the objective function to establish the final optimization model,and the genetic algorithm was used to optimize the solution,and the following conclusions were drawn:(1)Using COMSOL software to simulate the process of strengthening YT15 cemented carbide tools by pulsed electromagnetic field,it is found that the maximum value of the tool’s magnetic flux density and current density is mainly concentrated in the tip and blade area,and the axis of the excitation coil is Y in the entire space.The electric field and magnetic field at the center of the working cavity of the shaft are the strongest.They are distributed symmetrically along the Y axis in the whole cavity,and the electromagnetic field intensity at the edge of the working cavity gradually weakens as the distance increases.Therefore,in the actual processing of the blade,try to place the blade in the center of the copper pole in the working cavity,and the relatively best processing effect can be obtained by using external field parameters with lower power consumption.(2)Different pulsed electromagnetic field parameters have different effects on the tool life,but the service life of each tool specimen after pulsed electromagnetic treatment has been improved,which indicates that pulsed electromagnetic field treatment has a significant effect on the cutting performance of the tool.In order to carry out the subsequent experimental analysis,the best parameters of YT15 cemented carbide tool were optimized by statistical method.(3)The empirical model of turning process parameters on cutting force and tool surface friction coefficient was established by using MATLAB software.The significance test of the obtained model was carried out to improve the reliability of the model.Based on the empirical model,a multi-objective optimization model was established by using genetic algorithm to optimize the minimum main cutting force and tool surface friction coefficient,and the optimization solution was carried out according to the actual production and processing conditions,which could provide reference and guidance for the practical application of the technology. |
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