| Several kinds of transition metal nitrides were deposited by ion plating and the influence of ion implantation on their surface properties were investigated in this dissertation. The formation kinetics of chromium nitride was studied, subsequently the duplex CrN/Cr and graded CrNx coating were fabricated by ion plating, and the microhardness, tribological behavior and corrosion resistance were studied, respectively. The CrN/Cr coating could greatly improve the wear resistance of H13 steel. The graded CrNx coating has better corrosion resistance than CrN/Cr coating. SEM analysis showed that the columnar structure of graded coating was improved and there were no penetrable pinholes, which could reduce the electrolyte transfer to the substrate. TiN and ZrN coatings were prepared by planar rectangle cathodic arc deposition and were post-implanted by aluminum and rare-earth element with different doses respectively using an MEVVA ion source. It was indicated by the air oxidation measurement, X-ray photoelectron spectroscopy analysis that the oxidation resistance of TiN was greatly improved by aluminum ion implantation and increased with the ion dose. There was an alumina barrier formed in the top surface and could reduce the oxygen diffusion. Potentiodynamic polarization measurement showed that the corrosion resistance deteriorated after aluminum ion implantation, but after heat treatment the corrosion resistance was improved. It was believed that the deterioration was caused by the surface defects and remained aluminum, and heat treatment could reduce the defects and turned the aluminum into compact alumina barrier, thus the corrosion resistance was improved. After ion implantation the CIE (Commission International de l'Eclairage) L*a*b* values of TiN coating changed evidently. The luminance L* of TiN coatings increased and a* (green-red) and b* (blue-yellow) values decreased with increase of aluminum ion dose. The rare-earth elements yttrium and cerium ion implantation were used to improve the electrochemical property of ZrN coatings, and a model was found to interpret the mechanism of corrosion resistance improvement. The corrosion resistance of ZrN coatings increased with the dose increasing of yttrium or cerium. The principles of the improvement for two elements were similar. Ion implantation would change the microstructure and stress of the coating, diminish the interstitials. The barrier consisted of yttria or ceria on the surface would prevent the electrolyte from penetrating ZrN coating to the metal substrate. The zirconium particles and the pinholes would also be modified by the ion implantation, and therefore the corrosion resistance was improved. The air oxidation experiments revealed that yttrium ion implantation could greatly the oxidation resistance of ZrN coatings. It was found by GAXRD that the scale of as-deposited ZrN coating was made up of monoclinic ZrO2. After yttrium ion implantation, the tetragonal ZrO2 emerged, and its content advanced with yttrium ion dose, which indicated that yttrium could stabilize tetragonal. The formation of tetragonal ZrO2 could release the residual compressive stress, and made the oxide layer more compact. While after being implanted with cerium, the oxidation resistance of ZrN coatings deteriorated but rebounded with the dose increasing. The damage level of cerium ion implantation was higher than that of yttrium ion implantation, while the content of tetragonal ZrO2 increased with cerium ion dose, consequently the oxidation resistance improved in higher dose. Compared with as-deposited samples, the luminance L* of yttrium or cerium implanted ZrN coatings decreased, and a* (green-red) and b* (blue-yellow) values increased generally. It was believed that the colorimetric transfer related to the microstructure and especially the composition.
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