Through multisteps plating technique, various ion plated or reactive ion plated coatings were obtained in the laboratory. They are as follows: TiN/Y, Ti/Y, TiN/Ti/Y, Ti(R)N/Ti(R)/Y, TiN/YN/Y, Ti(R)N/YN/Y, Ti(R)N/Ti(R)/Ti, (here (R) presents the use of Y-containing Ti-alloy as evapouration source). By means of EPMA, IMA, AES, XRD, etc. Element and phase distribution in the coatings was studied. It was found that rear-earth Y in the coatings is concentrated at the coating/substrate interface. Y content at the interface area of Ti(R)N coating was about (0.2 - 0.5)wt%. The type and amount of the phases and the preferred orientations of the crystallites of the coatings were different. The Ti(R)N coating showed preferred orientation of TiN(lll) parallel to the sample surface, while the TiN coating had preferred orientation of TiN(200). The coating/substrate adhesive evaluated by scratch test and constant pulling rate tensile test showed that Ti(R)N coating was better than TiN coating without Y, However, Ti(R) coating is poorer than Ti coating through measuring the polarization curves of the coatings in several sorts of corrosion medium, it is obvious that IP-Ti coating has better corrosion-resistance than VP-Ti coating which may be due to negative bias which enable the IP-Ti coating becoming of higher degree of compactness and uniformity, pole figures of Ti(R)N and TiN coating show that Ti(R)N coating has main texture of TiN(112), TiN coating has TiN(110), that may be the main reason for better corrosion-resistance of Ti(R)N coating. Comparing the results of element profiles of the coating and the analysis of the change of alloying content at the top surface area of the evaporation source with evaporation time, one can proposed the enrichment of rare earth element Y at the interface may due to its selected evaporation and diffusion via some short circuits. Additionaly, the possible damage mechanism of TiN type coating under loading was also proposed.
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