Preparation And Properties Of Arc Ion Plating CrN Film

With high hardness,low internal stress,better thoughness,wear resistance and other excellent properties,CrN coatings is widely used in automobile,shipbuilding,aerospace and other fields.With the material service environment demanding,the traditional sigle-phase CrN unable to meet the operating condition in hardness,wear resistance and other aspects.The nanometer multilayer films which get by controlling the preparation parameters and film layer can improve the friction and wear resistance.However,with the thickness increased,the coatings internal stress increased which affect the adhesion and wear rate.So,prepare the CrN coatings with large thickness,high bonding strengh,low wear rate become the current research focus.In the paper,the Cr/CrN multilayer films were prepared on 6Cr13Mo low-carbon martensitic stainless steels by arc ion plating method.first,Using orthogonal experiment get the best preparation technology by optimizing the air pressure,current,bias.On this basis,deposite single-layer CrN film by changing thickness.Under the same deposition time,change the modulation cycle of Cr/CrN multilayers and optimize it.Based on the best modulation cycle,increase the deposition time get the Cr/CrN multilayers under different thickness,beside the basic performance test,study focus on the adhesion and wear rate.The results show as follow:1)We achieve the best films when parameters is that pressure is 1.4 Pa,current is 100 A and bias is 100 V in this experiments.2)With the thickness increased,surface topography of single-layer CrN film decreased radically.The hardness of single-layer CrN film increased with the thickness increased.With the thickness increased,the adhesion of single-layer CrN film declined as thickness increased.When thickness is 20 ?m,the adhesion of single-layer CrN film is only 13 N.The wear rate of single-layer CrN film increased radically with the thickness increased.3)The adhesion of Cr/CrN multilayer films under different modulation period are all more than 100 N,but the best is Cr/CrN multiayer films with 321 nm period possesses.the hardness of Cr/CrN multilayer films under different modulation period is similar.The wear rate of Cr/CrN multilayer films under different modulation period is within 2-4× 10-6 mm3/N·m,but,the wear rate of Cr/CrN multilayer films which modulation cycle is 569 nm is relatively low.4)With the thickness increased,surface topography of Cr/CrN multilayer films decreased,the compactness is great;the hardness of Cr/CrN multilayer films under different thickness is similar,are all more than 100 N;The wear rate of Cr/CrN multilayer films increased modestly under the same level with the thickness increased.5)The wear mechanism of single-layer CrN film is abrasive wear.However,the wear mechanism is sliding wear to Cr/CrN multilayer films.The wear rate of Cr/CrN multilayer films is one fourth to the wear rate of single-layer CrN film when the thickness is more than 10?m.