Resarch On Microstructure,Mechanical And Tribological Properties Of TaCN And VCN-Ag Nanocomposite Films

The hard films which are recognized as an important means of material surface modification covers the surface of the material to make the material exhibited higher hardness,better wear resistance and corrosion resistance.However,as the development of industrial,traditional binary transition metal nitride films have been unable to meet the more stringent service requirements.And diversification can further improve the performance of the films.Therefore,in this paper,a series of TaCN composite films with different carbon content and a series of VCN-Ag films with different Ag content were deposited by the magnetron sputtering system and their microstructure,mechanical and tribological properties were characterized by X-ray diffractometer,Raman spectrometer,atomic force microscope,scanning electron microscopy,transmission electron microscopy,energy dispersive spectrometer,nano-indentation and ball-on disc tribo-meter.The results showed that the deposited TaCN films exhibited a three-phase of face-centered cubic(fcc)Ta(C,N),hexagonal closed-packed(hcp)Ta(C,N)and amorphous CNx.With the increase of carbon content,the hardness of the TaCN films first increased and then decreased,after reaching a maximum of 33.1 GPa;the adhesion strength increased gradually;the coefficient of friction decreased monotonically and the wear property initially improved and then weakened at room temperature.The coefficient of friction of the TaCN film at 28.21at.%carbon decreased first,then increased and then decreased again and its high-temperature wear rate first decreased slightly and then increased,as the temperature increased from room temperature(RT)to 600°C.The TaCN film at 28.21 at.%carbon exhibited excellent an elevated-temperature tribological properties.The results showed that the deposited VCN-Ag films consisted of face-centered cubic(fcc)Ag,fcc-VCN,tetragonal(t)V₅CN and amorphous graphite and CNx phases,and nano-crystalline Ag was dispersed in the films.The addition of Ag below 0.72 at.%into the film increased the hardness,however,the hardness decreased rapidly when the Ag content was increased furtherly.The initial introduction of Ag into the film led to the lowering of the film's room-temperature wear rate,nonetheless,the wear resistance deteriorated when the Ag content was further increased.However,the friction coefficient of the films at room temperature increased monotonically as the content of the Ag increased.As for elevated temperature tribological properties of the film at 3.03 at.%Ag,there was an initial increase in frictional values but,when the temperature was above 300?the frictional values declined.More so,the wear rate increased monotonically when the temperature increased from 100?to 500?.