Research On Innovative Design Of The Micro Groove On The Rake Face Of Cemented Carbide Tool Cutting 40CrMnMo

The region near the cutting edge on the rake face of tools is a highly concentrated area of the heat load and mechanical load during the cutting process,with poor working conditions.And it has significance influence on tool life.The design of the micro structure of the rake face has an important influence on the improvement of the comprehensive cutting performance of tools.In this paper,Special cemented carbide coated turning tool for oil country tubular goods(OCTG)40Cr Mn Mo used by enterprises(hereinafter referred to as "original turning tool")is taken as the research object.Considering "reduce the cutting temperature and increase the tool life" as the main goal,an innovation design method of micro groove on the rake face of tools based on temperature field is proposed.A set of new cemented carbide coated micro groove turning tool with a comprehensive cutting performance better than the original turning tool based on this method(hereinafter referred to as "micro groove turning tool").And this paper focuses on the comprehensive cutting performance of the new micro groove turning tool(brittle damage resistance,tool life,cutting temperature,cutting force and machined surface quality etc.),cooling and wear mechanism.An innovation design method of micro groove on the rake face of tools based on temperature field is proposed and established.Taking Deform-3D as the cutting simulation platform,the finite element numerical simulation is carried out on the cutting process of the original turning tool.After the data extraction and processing,the effective point cloud data of the temperature field in the initial condition of the numerical simulation is obtained.Taking NX 8.5 as the 3D modeling platform,the NURBS temperature field grid surface is generated by the secondary development of the platform.Based on deform-3D cutting simulation platform and ANSYS Workbench finite element analysis platform,reasonable test schemes are established.Groove shape key parameters on the rake face are corrected and optimized.It provides a theoretical basis for the design of the micro groove turning tool.Numerical analysis method of brittle damage of cemented carbide micro groove turning tool based on Peridynamic(PD)theory is proposed and established.According to the geometric characteristics and thermal physical properties of the special-shaped surface of cemented carbide tools,under the Microsoft Visual Studio 2015 integrated environment,the PD modeling and numerical analysis of the original turning tool and the new micro groove turning tool are realized by C++ programming language.Finally,with the help of MATLAB visualization module,the visualization of the PD numerical analysis results of the two tools realized.By the displacement and its trend of the discrete material points,the damage of region near the cutting edge on the rake face of turning tools is analyzed.The mechanical reliability of the original turning tool and the micro groove turning tool under the three-axis impact load during the cutting process is compared.It provides theoretical support for manufacture of the new micro groove turning tool.Research on the basic theory of the cutting process of the new micro groove turning tool cutting 40 Cr Mn Mo.The mechanical model of the new micro groove turning tool cutting OCTO 40 Cr Mn Mo is established.Cutting model of micro groove turning tool cutting 40 Cr Mn Mo based on Oxly-Welsh theory is established.With the help of the finite element simulation platform,the friction model of the process of the micro groove turning tool cutting 40 Cr Mn Mo is established.By the results of cutting experiments and theoretical analysis,considering the influence of size effect,strain hardening effect and thermal softening effect of the shear zone on cutting process,and the deformation mechanism of the workpiece material and the thermal and mechanical properties are revealed and analyzed.An evaluation method of micro groove design based on cutting performance of tools is established.In this paper,by studying the effects of micro groove on the rake face on the thermal and mechanical model in the cutting process,thermal mechanical model,the relationship of main mechanical parameters and cutting energy of shear deformation,generation,transmission and transformation of cutting energy in the cutting process and the wear morphology and the chemical composition of flank and rake faces,cooling mechanism and tool wear mechanism of micro groove turning tool are revealed.Then evaluation method of micro groove design based on cutting performance of tools taking "reduce cutting temperature and improve tool life" as the main goal is established.This paper establishes an innovation design method of micro groove on the rake face of tools based on temperature field through the combination of theoretical analysis and calculation,sample preparation and measurement,mathematical modeling and numerical simulation,case verification and performance evaluation.Based on the design method,a new cemented carbide coating micro groove turning tool is designed and pepareted.Through cutting tests and theoretical analysis,it is found that the cutting temperature of the new micro groove turning tool is reduced and its life increases obviously.And the main cutting performance is better than that of the original turning tool.The cooling mechanism,the wear mechanism,the heat and mechanical model of the micro groove turning tool are revealed and obtained.Finally,the innovation design method of micro groove on the rake face of cemented carbide tools cutting 40 Cr Mn Mo has certain referentical significance.