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In this paper, Zr(Hf)xCN coatings were deposited onto 316L stainless steel (316L SS) substrates at 400 °C using the radio-frequency (R.F.) magnetron sputtering technique with Hf-Zr-C composite target materials. The influence of Hf element content on microstructure, mechanical properties, and corrosion resistance and platelet interaction with the surface of Zr(Hf)xCN coatings were then investigated. The results indicate that the microstructure, mechanical properties, and corrosion resistance of coatings depend on their chemical composition. Corrosion resistance and platelet interaction with the surface could be improved by adding Hf to the Zr2CN. By optimizing the Hf-Zr-C ratio, Zr(Hf)xCN coatings with excellent corrosion resistance were obtained. The ZrHfCN-3 coating with a Hf element content of 7.33% possesses excellent mechanical properties and good corrosion resistance. The result of the platelet interaction with the surface confirms that Zr(Hf)xCN coatings have better platelet interaction with the surface than 316L SS. [ABSTRACT FROM AUTHOR]

In the paper, by using radio frequency (RF) magnetron sputter technology, the HfC coating grew on a 316L stainless steel substrate in an Ar atmosphere at various substrate bias voltages from 0 to −200 V. From the X-ray diffraction (XRD) and transmission electron microscopy (TEM) experiments, the HfC coatings were well crystallized and (111) preferential growth had been successfully obtained by controlling bias voltage at −200 V. Nanoindentation experimental results for the prepared HfC coatings indicated that they possessed the maximum nanohardness due to the formation of the (111) orientation. The results of electrochemical measurements displayed that 316L stainless steel (316L) coated with the HfC coatings had better corrosion resistance than bare 316L. With the bias voltage increasing to −200 V, adhesion of the 316L substrate with the HfC coating could be greatly improved, as well as corrosion resistance. The antithrombogenicity of the HfC coatings was identified by platelet adhesive and hemolytic ratio assay in vitro. It was shown that the hemocompatibility of coated 316L had been improved greatly compared with bare 316L and the HfC coatings possessed better antithrombogenicity with the bias voltage elevating above −150 V. [ABSTRACT FROM AUTHOR]

The short service life of the Ti/BDD coated electrode is the main reason that limits its practical use. In this paper, the effect of structural change on the service life was studied using Ti/BDD coated electrodes prepared with the arc plasma chemical vapor deposition (CVD) method. It was found that the microstructural defects and corrosion resistance of BDD coatings were the main factors affecting the electrode service life. By optimizing the process parameters in different deposition stages, reducing the structural defects and improving the corrosion resistance of the BDD coating were conducted successfully, which increased the service life of the Ti/BDD coated electrodes significantly. The lifetime of the Ti/BDD samples increased from 360 h to 655 h under the electrolysis condition with a current density of 0.5 A/cm2, with an increase of 82%. [ABSTRACT FROM AUTHOR]