Tribological Properties Of CrN And AlCrN Thin Films Deposited By Physical Vapor Deposition

Physical vapor deposition is an important surface engineering technology to improve the tribological properties of mechanical parts.In this paper,CrN and AlCrN films were prepared by cathodic arc ion plating in consideration of the high temperature wear problem of dies and cutting tools,and were subjected to normal temperature friction and wear tests,then the AlCrN films were treated in atmosphere and vacuum respectively.Four kinds of AlCrN films with different parameters deposited by magnetron sputtering were heat treated in atmospheric environment.Selected parameters: Ar gas flow 100 sccm samples for high-temperature friction test.The morphology,microstructures,hardness and phase composition of the films were characterized by 3D profilo-meter,Scanning electron microscope,nanoindenter,X-ray diffraction(XRD).The High Temperature Tribological Properties and mechanism of nitride films were discussed.The results are as follows:(1)The CrN thin films deposited by cathodic arc ion plating have smooth surface and few defects.The nano hardness and elastic modulus of CrN thin films are28 GPa and 350 GPa,respectively.When the grinding ball is Si3N4 ceramic ball,the main wear mechanism of CrN films is abrasive wear,with a small amount of oxidation and adhesive wear and wear mechanism of 316 L stainless steel is mainly abrasive wear and plastic deformation,accompanied by a small amount of oxidation and adhesive wear.When the grinding ball is 52100 steel ball,the main wear mechanism of CrN films is adhesive wear,accompanied by a small amount of oxidation and the wear mechanism of 316 L stainless steel is mainly adhesive wear,accompanied by a small amount of oxidation and abrasive wear.(2)The AlCrN thin films with smooth surface deposited by cathodic arc ion plating is composed of three phases: CrN,AlCrN and AlN.Under the condition of dry friction,the AlCrN films has good resistance to high load friction,and the wear mechanism is abrasive wear.Under the condition of PAO4 lubricating oil,the wear rate of the AlCrN films increases with the increase of the load,and the wear mechanism is mainly adhesive wear and slight abrasive wear.In the atmosphericenvironment,the oxidation phase Cr2O3 began to appear at 800?,and AlCrN films can still maintain high nano hardness and elastic modulus at 800?,15 GPa and260GPa,respectively.(3)The four parameters of AlCrN films deposited by magnetron sputtering have no obvious difference,and the surface of AlCrN films overall smooth and compact.The AlCrN films is composed of three phases: CrN,AlCrN and AlN.The oxidation products Al2O3 and Cr2O3 of Al and Cr can effectively improve the oxidation resistance and mechanical properties of the films.The friction coefficient of the AlCrN film with Ar/N2 gas flow rate of 100sccm/50 sccm were higher than 20? at high temperature.The main wear mechanism of AlCrN films under 20? is abrasive wear,adhesive wear and oxidation wear,and under the condition of high temperature,the wear mechanism is plastic deformation,abrasive wear,oxidation wear and adhesive wear of the composite wear.