Research On Magnetron Sputtering CrN Coating And Performance Of High Speed Steel Tool

High speed steel tool as a cutting tool,its life to the normal operation of the whole system plays a decisive role,especially in automatic production and all kinds of CNC machine high speed steel cutting tools,processing of high precision,wear-resisting performance good.How to improve tool cutting performance and service life effectively becoming the research focus of modern manufacturing industry.Magnetron sputtering is one of the important research directions of surface technology,which can significantly improve the comprehensive performance of the workpiece.In this paper,high speed steel tool is selected as the research object,and CrN coating is deposited on the surface of high speed steel tool by RF magnetron sputtering.Influence of target power,coating time and nitrogen flow on CrN coating performance are studied by orthogonal test design,and optimum technological conditions for preparing CrN coating are obtained.Using single factor analysis method,research different technological parameters on the CrN coating deposition rate,morphology,microhardness,film adhesion,organization structure and chemical composition.Film thickness,bonding force,surface roughness and microhardness of the coating are measured by step meter,scratch meter,roughness measuring instrument and microhardness tester.X-ray diffractometer is used to study the coating structure,scanning electron microscopy.SEM is used to observe the coating surface and section morphology.Discussing tribological properties of non-coated cutting tool,the common technology coated tools,optimization of coated tool.Grinding crack depth,grinding crack width and friction coefficient with parameters vary are researched.The research shows:Optimum process parameters of the coating are target power for 150W,coating time for 125min,nitrogen flow for 40sccm.Hardness of CrN coating prepare under the optimal process,microhardness for 1207HV_0.1,thickness of the film for 3.11um,surface roughness for 0.540um,binding force for 31.6N.Coating for three pyramid shape,surface smooth smooth,outline clear and compact structure,small particle size,film adhesion and hardness higher,film adhesion compared with the traditional process is increased by 6%.Coating has obvious CrN?111?preferred orientation and the ratio of the Cr and the N atom number closing to 1:1.Wear test showed that the coated tool wear serious,on both sides of coated cutting tool grinding crack only slight furrow and less abrasive dust accumulation,grinding crack depth,grinding crack width,the coefficient of friction are smaller.High load conditions?load of 5N?,ordinary coated cutting tool surface spalling failure,grinding crack depth,grinding crack width,for 4.12um,720.4um,friction coefficient for 4.12,respectively,and the optimization of coated cutting tool grinding crack on the surface of a shallow color,wear light,grinding crack depth,grinding crack width for 2.25um,570.8um,friction coefficient for 2.25.Therefore,the tool performance is improved significantly by optimizing the process deposition of CrN coating on the surface of high speed steel tool,which provides reference for the surface strengthening treatment of high speed steel tool.