Effect Of Plasma Enhanced Magnetron Sputtering Process Parameters On The Structure And Properties Of CrN Coatings

CrN coating has been widely used in the mechanical industry,but the CrN coating prepared by traditional magnetron sputtering technology has the disadvantages of low ionization rate and low hardness.Plasma-enhanced magnetron sputtering?PEMS?significantly increases the plasma density,and can produce CrN coatings with good compactness,high hardness,and good wear resistance.However,the influence of process parameters on the structure and properties of CrN coatings produced by PEMS The research needs to be further studied.In this paper,the effects of different bias currents and N₂ flow rates on the structure and properties of CrN coatings.prepared by plasma-enhanced magnetron sputtering are studied.The results show:1)As the bias flow increases,the CrN coating is more dense and the columnar crystals are finer.The coating phase changes from Cr through Cr₂N to CrN;the deposition rate is firstly reduced and remains basically unchanged;the binding force under low bias flow is higher than the binding force under high bias flow;hardness?H?,equivalent Young's modulus?E*?,H/E and H³/E*² increased with the bias current,reached a maximum at 3.0 A,and did not change significantly after 3.0 A;the friction coefficient increased first and then decreased,reaching a maximum of 6.10 nm at 1.5A.The wear rate of the coating is basically unchanged after the first reduction;however,the maximum value of the friction coefficient is close to 6.0 A,the wear rate is low when the bias flow is 4.5 A,and the hardness and elastic modulus are close to the maximum value to obtain the best overall performance.2)As the N₂ flow rate increases,the phase structure of the coating gradually transitions from the Cr phase to the CrN phase;the change of the N₂ flow rate mainly affects the phase structure of the coating,but it is not particularly affected the preferred orientation of the coating.Obviously,the surface and cross-section densities of CrN coatings become smaller firstly and then become larger;the deposition rate of CrN coating remains basically unchanged;the adhesion rises first and then decreases,and the maximum and minimum values are obtained at 15 sccm and 30 sccm of N₂flow rate,respectively;The hardness of the coating rises linearly when the N₂ flow rate increases from 15 sccm to 25 sccm,and reaches a maximum value of 32 GPa at25 sccm.When the hardness rises from 25 sccm to 40 sccm,there is a more obvious decrease in hardness;The changed of equivalent elastic modulus of the coating E*is the same as that in hardness.The maximum value of 350.4 GPa is obtained at 25 sccm of N₂ flow rate,but the E*drop is faster than the hardness drop at 25 sccm to 40 sccm.H/E and H³/E*² showed the same trend with the change of hardness;the wear rate of the coating and the grinding ball first decreased and then rose,and the coating wear was mainly in the form of adhesive wear.