Structure and Properties of Periodic Multilayer Metal/nitride Coatings Deposited from Filtered Vacuum-arc Plasma Using Ti-Al-Y Cathode

Abstract

The composition, structure, hardness and wear resistance of periodic multilayer metal/nitride coatings deposited from a filtered vacuum-arc plasma using $\mathrm{T}\mathrm{i}_{0.47}\mathrm{A}1_{0.51}\mathrm{Y}_{0.02}$ cathode by the PIII& D method were investigated. The coating period was changed in the range of 35-300 nm by changing the duration of the periodic feeding (pumping) of nitrogen into the vacuum chamber. The mechanical characteristics of multilayer metal / nitride and single-layer nitride coatings are compared. Single-layer nitride coatings are characterized by a fairly high hardness of 34-36 GPa. The hardness of the multilayer coatings is lower and decreases from 24 to 19 GPa with decreasing period of the composition. The introduction into the composition of nitride coatings of more plastic metal layers does not increase the criterion H/E, which is in the range of 0.07 to 0.09. Due to the high hardness, single-layer coatings have high resistance to abrasive wear, but are destroyed by cavitation due to cracks and pitting peels. Multilayer coatings were slightly better in the cavitation test due to the less pronounced columnar structure, but do not withstand abrasive effects.