Research On Cutting Performance And Wear Characteristics Of Coated Tool

The application of a coating on the cemented carbide tool substrate can decrease cutting force,lessen tool wear,and enhance tool longevity.Notably,it has a thermal barrier effect,which affects cutting heat conduction and temperature,making it a current research focus in the field of cutting processing.This research examines the cutting performance of Ti Al Si N single-layer and Ti Al N/Ti Al Si N double-layer cemented carbide coating tools while machining nickel-based superalloy Inconel718.It analyzes cutting force,cutting temperature,and tool wear.To investigate the impact of different cutting speeds and coating thicknesses on the performance of coated tools,2D and 3D simulation calculation models of the turning process of cemented carbide coated tools were developed using the finite element method.The simulation outcomes were then experimentally validated to confirm the credibility of the results.The wear form and wear mechanism of the coated tool were analyzed using the experimental sampling data,and the tool life was predicted based on the CPSO-RBF neural network.The research covered the following three main aspects:(1)A thermomechanical dual-zone analysis model based on the moving heat source theory was established to predict the temperature distribution of coated tools during cutting.An analytical model of cutting temperature distribution in the three deformation zones of the coated tool was developed and compared with simulation results.It was observed that incorporating the three deformation zones into the tool temperature model can enhance the calculation accuracy of the rake face temperature,leading to more realistic simulation results.This helps to more accurately predict the maximum temperature distribution on the rake face,as well as the temperature distribution inside the coated tool and workpiece.(2)The multi-coating equivalent layer method was used to convert the Ti Al N/Ti Al Si N double-layer coated tool into an equivalent single-layer composite coated tool based on steady-state and transient cutting heat conduction models of coated tools.The equivalent coating method results showed that the cutting performance of Ti Al N/Ti Al Si N doublecoated cemented carbide tools was superior to that of Ti Al Si N single-coated tools.Moreover,the cutting temperature measurement experiment revealed that under different coating thicknesses,the rake face temperature of the Ti Al N/Ti Al Si N double-layer coated cemented carbide tool is lower than that of the Ti Al Si N single-layer coated cemented carbide tool.(3)The wear model of the coated tool was established using the finite element method to study the cutting wear characteristics of the tool.It combined experimental sampling data to analyze the failure mechanism of the coated tool and use the neural network to predict the tool life.The research showed that the wear degree of the Ti Al Si N coated tool increases with the increase of cutting speed,the main wear forms of the rake face are crescent crater,coating peeling,bond accumulation,and micro chipping.The flank face is mainly affected by bond wear and oxidative wear.The thicker the coating,the more the internal temperature of the coating drops,which can slow down the wear of the coating and prolong the tool’s life.The CPSO-RBF neural network model for tool life prediction yielded an average relative error of 11.57%,which was better than the previous prediction results using the BPRBF neural network model.