| As a kind of protective coating which can effectively improve the tool service life and reduce energy consumption,tool coating has attracted more and more attention.Since the seventies of the 20th century,tool coatings have developed rapidly,from binary protection coatings to multi-layer nano-composite protection coatings,people have made great achievements.Cr-Si-N coating which is a kind of high hardness,low friction coefficient,high temperature oxidation resistance and other advantages of the protective coating,is particularly concerned by people,but also in industry has been a certain range of applications.But with the research and expansion of the coating,we try to reduce the friction coefficient of the tool coating of Cr-Si-N to further reduce the friction between the edge and the workpiece,and to improve the tool life,which triggered a large number of researchers to focus on the research.To improve the coatings properties,many research groups study how to reduce the friction coefficient of Cr-Si-N coating by adding W,C,Y and other elements,but the results were not corresponded with their idea.The significance of this paper is to reduce the friction coefficient of the coating to increase the service life of the tool,and to study the effect of O element on the coating.The research idea of this paper is to add Al element on the basis of Cr-Si-N to reduce the friction coefficient of the coating and improve other properties.In addition,the effect of O content on the performance of Cr-Si-N coating was also studied.Using the multi-arc ion plating deposition technology to prepare Cr-Si-N,Cr-Al-Si-N,Cr-Si-O-N coatings by changing the arc current or O2 flow rate.All the coatings are tested by XRD,SEM,EDS,electrochemical workstations.By changing the CrSi arc current?50 A-90 A?to prepare the Cr-Si-N coatings and study its properties.The results show that when the arc current is 70A,the hardness is the highest?about 3120Hv?,the friction coefficient is minimum,and the corrosion resistance at high temperature is the best.By changing the CrAl Si arc current?50 A-90 A?to prepare the Cr-Al-Si-N coatings and study its properties.It is concluded that the friction coefficient can be lower than 0.35 when the current is at 80A.Compared with Cr-Si-N coatings,Cr-Al-Si-N has a lower friction coefficient and lower hardness.By changing the O2 flux rate to prepare the Cr-Si-O-N coatings and study its properties.The results show that O element has a great influence on the coating.After the study of this experiment,the hardness of the nano-composite tool coating Cr-Si-N can be as high as 3120 Hv,and has good corrosion resistance and high temperature oxidation resistance.With the addition of Al element,the friction coefficient of the coating is reduced from 0.45 to 0.35,which will greatly increase the service life of the tool coating.However,with the incorporation of O element,the performance of the coating is seriously affected.Therefore,the presence of O element should be avoided as much as possible during the preparation of the Cr-Si-N coating.. |
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