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The work reports on the morphologies and the tribological properties of MoS 2 films deposited onto the as-deposited or textured TiN and WC interlayers. The closed-field unbalanced magnetron sputtered MoS 2 film exhibited dense structure without obvious voids or columnar morphology. Meanwhile, plenty of MoS 2 nanowires or nanorods were grown on the film surface. With the laser-textured TiN or WC interlayer introduced, both the textured TiN/MoS 2 film and WC/MoS 2 film exhibited a long lubricating life higher than 8.0 × 105 sliding cycles, much higher than that for the un-textured films or pure MoS 2 film. • MoS 2 films with textured TiN, WC interlayer were deposited by a closed-field unbalanced-magnetron sputtering system. • The deposited MoS 2 film exhibited a dense structure with plenty of nanowires or nanorods grown between the MoS 2 columnar. • The textured TiN/MoS 2 film and WC/MoS 2 film exhibited a long lubricating life higher than 8.0 × 105 sliding cycles. [ABSTRACT FROM AUTHOR]

Many failures and anomalies of spacecrafts originated from space environmental factors. Meanwhile, MoS 2 based films have been widely used in space technology as solid lubricants. In this paper, the compact MoS 2 -Sb 2 O 3 composite film was rf-sputtered and exposed in low earth orbit (LEO) environment, which was aboard the exterior of Shenzhou-7 Manned Spaceship (SZMS-7). The results revealed that the space exposure effect on MoS 2 -Sb 2 O 3 composite film mainly exhibited the oxidation at the film surface layer less than 3.5 nm. No severe oxidation and cracking phenomena were observed from the space-exposed MoS 2 -Sb 2 O 3 composite film, which was normal for many space materials. Namely, the MoS 2 -Sb 2 O 3 composite film exhibited a better capability resistant to LEO space environment. [ABSTRACT FROM AUTHOR]

The sputtered CrN coatings, which were bombarded by the energetic Cr-ion via filtered arc ion plating layer by layer, were prepared to improve the corrosion resistance of the coated samples. By controlling the times of Cr ion bombardment, the influence of the Cr ion bombarding of the sputtered CrN were investigated from the aspect of the microstructure and corrosion behavior. The results indicated that the CrN film showed a suppressed effect on the coarse columnar structure and a more compact structure with lower porosity by introducing the Cr-ion bombardment. Potentiodynamic polarization curves showed that the CrN coated samples had an obvious improved corrosion resistance after the energetic Cr ion bombardment. With the bombarding times of Cr ion increasing from four to ten, the corrosion resistance of CrN coated samples showed a further improvement with corrosion potential increased about 100 mV and the corrosion current density decreased more than one order of magnitude when compared with the non-bombarded CrN coating. [ABSTRACT FROM AUTHOR]

CrN nanocone-array supported WS 2 film was prepared by depositing a nanocone-array CrN interlayer and then a radio frequency sputtered WS 2 layer. The microstructures of the deposited films were investigated by field emission scanning electron microscopy and grazing incidence X-ray diffraction. The CrN nanocones array have an average period of about 150 nm, and the height of each nanocone is about 100 nm. The CrN nanocone array textured WS 2 film presented an improved lubricating lifetime due to the regular CrN nanocone arrays acting as a good reservoir of the WS 2 lubricates. [ABSTRACT FROM AUTHOR]

MoS 2 film deposited was deposited by closed-field unbalanced-magnetron sputtering (CFUBMS), and its structural and tribological properties were modified by the heat treatment at temperature range of 100–500 °C in vacuum environment. Results revealed that as-deposited MoS 2 film was composed of MoS 2 plus a little MoO 3 with a dense amorphous-like structure. After the vacuum heat treatment, MoS 2 film was still very compact, but its microstructure was changed from amorphous-like to nano-crystalline states with the increase of heat treatment temperature. As a result, a MoS 2 film with a microstructure of MoS 2 nanocrystals embedded into its own amorphous matrix was obtained at middle temperature of 200 °C. Furthermore, MoO 3 phase in the film was reduced to MoO 2 after the vacuum heat treatment at high temperatures of 400 and 500 °C. Friction tests revealed that the wear resistance of MoS 2 film in vacuum environment was significantly improved by the vacuum heat treatment at suitable temperature. The wear life of vacuum-heat-treated MoS 2 film at 200 °C for 3 h was ~6.2 × 105 r, about four times longer than that of as-deposited MoS 2 film. Unlabelled Image • Amorphous-like MoS 2 film changed structure to nanocrystal states, embedded into matrix to improve wear resistance by vacuum-heat-treatment. • Its structure and wear resistance may be significantly modified by vacuum-heat-treatment. • Film structure changed from amorphous-like to nanocrystal states by vacuum-heat-treatment. • A special structure of MoS 2 nanocrystals embedded into its own amorphous matrix was obtained at suitable temperature of heat treatment. • Wear life of vacuum-heat-treated MoS 2 film at 200 °C was about four times longer than that of as-deposited MoS 2 film. [ABSTRACT FROM AUTHOR]