Effect of Auxiliary Enhanced Magnetic Field on Microstructure and Mechanical Behaviors of Multilayered CrN/AlCrN Films

CrN/AlCrN nano-multilayer films can combine the advantages of CrN and AlCrN films through film structure modulation using multi-arc ion plating technique. Auxiliary enhanced magnetic field may improve arc spots velocity and be beneficial to flexible structure modulation in this paper. An inductance coil was installed behind the CrAl target to further enhance the magnetic field. Then, CrN/AlCrN nanoscale multilayers were deposited on the single crystal silicon, M2 high-speed steel and the 304 stainless steel samples by the magnetic field enhanced multi-arc ion plating technique. The morphology and crystal structure of the film after deposition were analyzed, and the effects of magnetic induction intensity under different coil current on the bond strength, wear resistance, hardness and corrosion resistance of the film were studied. The results show that the number of large particles on the surface of the film is significantly reduced compared with that without magnetic field enhancement. The crystal structure of the thin film is a rocksalt-type cube with (111) and (311) preferred orientations. At the same time, increasing the coil current can improve the film compactness. With the increase of coil current from 0.3A to 1.2A, the microhardness and corrosion resistance of the film are improved due to the compact structure. However, the bond strength increases first and then decreases due to the increase of the stress caused by excessive ion impact. The friction coefficient and wear width of the film are the minimum when the coil current is 0.6A.