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Ti/TiN multilayer film was deposited on uranium surface by arc ion plating technique to improve fretting wear behavior. The morphology, structure and element distribution of the film were measured by scanning electric microscopy (SEM), X-ray diffractometry (XRD) and Auger electron spectroscopy (AES). Fretting wear tests of uranium and Ti/TiN multilayer film were carried out using pin-on-disc configuration. The fretting tests of uranium and Ti/TiN multilayer film were carried out under normal load of 20 N and various displacement amplitudes ranging from 5 to 100 μm. With the increase of the displacement amplitude, the fretting changed from partial slip regime (PSR) to slip regime (SR). The coefficient of friction (COF) increased with the increase of displacement amplitude. The results indicated that the displacement amplitude had a strong effect on fretting wear behavior of the film. The damage of the film was very slight when the displacement amplitude was below 20 μm. The observations indicated that the delamination was the main wear mechanism of Ti/TiN multilayer film in PSR. The main wear mechanism of Ti/TiN multilayer film in SR was delamination and abrasive wear.

The Ti/TiN multi-layer film was prepared on the depleted uranium (DU) substrate by cathodic arc ion plating equipment. The character of multi-layer film was studied by SEM, XRD and AES, revealed that the surface was composed of small compact particle and the cross-section had a multi-layer structure. The fretting wear performance under different frequencies was performed by a MFT-6000 machine with a ball-on-plate configuration. The wear morphology was analyzed by white light interferometer, OM and SEM with an EDX. The result shows the Ti/TiN multi-layer film could greatly improve the fretting wear performance compared to the DU substrate. The fretting wear running and damaged behavior are strongly dependent on the film and test frequency. The fretting region of DU substrate and Ti/TiN multi-layer under low test frequency is gross slip. With the increase of test frequency, the fretting region of Ti/TiN multi-layer change from gross slip to mixed fretting, then to partial slip.

In the present paper, Cr, CrN single-layer films and Cr/CrN multilayer films were deposited on iron and silicon wafer substrates by means of unbalanced magnetron sputtering. The film thickness was measured using surface profile meter. The porosity ratio was calculated using coulometric method based on the polarization curves obtained in the 30g/L NaCl solution at room temperature. Moreover, the corrosion resistance of the sample in a 350°C water vapor atmosphere was also analyzed. The thickness of all films ranged from 1.03 to 1.54 micrometer. The porosity ratio of the Cr and CrN single-layer film were 3.72% and 5.83%, respectively. The porosity of the Cr/CrN multilayer film decreased to 0.39%. The results showed that the Cr/CrN multilayer films had better protection than the Cr and CrN single-layer films.