Preparation Of Diamond-like Carbon Films Doping With Cu,Zr,N And Investigation Of Their Properties

Diamond-like carbon films have excellent mechanical properties,tribological properties and chemical inertness,which make them have great application in industry and medical science and other fields.The process parameters have a great influence on the mechanical properties of diamond-like carbon films,among which adhesion between film and substrate is the most important.Films can easily peel off from substrates,which limit diamond-like carbon films to application.Doping elements can effectively improve the adhesion strength between the thin film and substrate,which is key technology for comprehensive application.So,to explore the reasonable preparation technology becomes a focus.This article adopts the ion source auxiliary direct current(DC)magnetron sputtering and ion source assisted radio frequency(RF)magnetron sputtering method,which can prepare diamond-like film with different copper content,Zr content and nitrogen content doped.Then,the composition and structure,mechanical properties of films,tribological properties and corrosion resistance are analyzed.The following conclusions can be drawn according to comprehensive tests and analysis results:(1)For diamond-like carbon films with different content of copper doped,as electric current of the copper doped increases,copper content in diamond-like films is increase,but film thickness and deposition rate don't vary obviously.With copper content increasing,the ID/IG in diamond-like carbon film decrease at first,and then increase.However,sp3 content firstly increases and then decreases.Affected by sp3 content,diamond-like carbon films with copper doped hardness and elastic modulus increase firstly and then decrease.The adhesion strength of the films increased with the increase of copper content at first and then decrease.The surface roughness and friction coefficient decrease gradually with the increase of copper content.Because of the influence of hardness and elastic modulus,wear rates increase at first and then decrease.The increase of copper content is against corrosion resistance of diamond-like carbon films.In brief,when copper content in diamond-like carbon films is 4.6at %,the adhesion is best,and hardness and elastic modulus is higher,friction coefficient and wear rate are lower.(2)For diamond-like films with zirconium(Zr)doped,as Zr power increases,Zr content increases linearly.At the same time,as the Zr power increases,diamond-like carbon film with Zr doped thickness and deposition rate increase at first and then becoming stability.When Zr content increases from 4.9at % to 16.3at %,ID/IG increases gradually,and sp3 content in Zr doping diamond-like films decreases,and the hardness gradually decline from 16.2GPa to 10.1GPa.When Zr content continues to increase,ID/IG decreases,and hardness increases to 15.0GPa.The friction coefficient of diamond-like films with Zr doped is lower than stainless steel substrate,so wear rate is.The minimum friction coefficient of diamond-like carbon films with Zr doped is 0.07.When Zr content increases from 4.9at% to 16.3at%,ID/IG increases gradually,and sp3 content in diamond-like films with Zr doped decreases.Because diamond-like carbon film density reduces,corrosion resistance becomes worse.However,when ID/IG decreases,sp3 content increases,and the corrosion resistance of diamond-like carbon films becomes better.With a certain range of Zr content,the diamond-like carbon films' corrosion resistance is better than stainless steel substrate.(3)For diamond-like carbon films with nitrogen doped,when N2 gas flow rate increases,nitrogen content in diamond-like films increases gradually,diamond-like carbon films with nitrogen doped thickness and deposition rate increase gradually.Affected by the internal stress,as the nitrogen content increases,the adhesion intensity between films and substrates become worse and worse.When nitrogen content increases at a certain range,ID/IG decline.When nitrogen content continiue to increase,ID/IG increase.So sp3 content increased when nitrogen content at a certain range,and then sp3 content decreases.Vickers hardness increases when nitrogen content at a certain range 0 and 21.0at%,and then decreases.The friction coefficient and wear rate increase at first with the nitrogen content increasing,and then they decrease.With the increase of nitrogen content in a certain range,corrosion resistance of diamond-like carbon films with nitrogen doped enhances.Beyond the range,corrosion resistance is weaker.When nitrogen content is in an appropriate range,the corrosion resistance of films can be improved.