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Recently, research has been conducted on nanocomposite thin films containing new additive elements in ZrN. In this paper, a method for depositing ZrCuSiN nanocomposite coatings using a ZrCuSi single target is presented. The ZrCuSi target that was used to easily deposit a ZrCuSiN coating in a mixed gas atmosphere (Ar + N2) was produced by a simple arc melting method (casting process). The effect of the nitrogen content was investigated by depositing a ZrCuSiN coating using alloy targets at various nitrogen gas flow rates (2, 4, 6, and 8 sccm). X-ray diffraction analysis of the ZrCuSiN coatings revealed a ZrN structure with a preferable orientation (200). As the nitrogen flow rate increased, the formation of o-Zr3N4 was dominant in the ZrN formation. A nitrogen gas flow rate of 4 sccm produced a coating with optimal ZrN and a-Si3N4 coordination and maximum hardness (41 GPa). Reciprocal friction tests of all coatings and uncoated carburized SCM415 steel in a 5W30 lubrication atmosphere demonstrated that the 4 sccm coating had the lowest friction coefficient (0.002). Therefore, our method has the potential to be an alternative surface coating technique for materials used in automotive engine parts and various other wear protection applications.

Generally, thin-film metal glass (TFMG) is deposited using two or more elemental targets. Thus, achievement of a homogeneous coating during mass production is difficult. As a new method of TFMG deposition, a single target with high glass-forming ability (GFA) has been used to improve the sputtering process, facilitating easy processing and broad application of sputtering targets. In this study, three kinds of targets (i.e., cast, amorphous, and crystalline targets) are prepared via casting and powder processes. The thermal and mechanical properties of the three targets prepared using the various methods are investigated, and the crystalline target is found to be the most thermodynamically and mechanically stable of the three alternatives. In addition, for TFMG deposited using the microcrystalline target, excellent compositional uniformity between the target and coating is achieved. Therefore, this study experimentally demonstrates that a fine crystalline target is most suitable for use as a multi-component single target in GFA manufacturing methods. These findings are expected to facilitate commercial use of TFMGs.

Recent findings of R&D for powertrain components concerning friction and wear reduction are described in this chapter. These are realized through lubrication technology of coating and heat treatment, which are fit for this book. In the first part, nano-complex coatings for parts of future mobility are presented with their friction and wear behavior. The application of an alloying target was proposed to promote the commercial use of nanocomposite coatings. In the second part, the importance on pre-treatments-related silicon oxide-diamond-like carbon (SiO-DLC) coating for the smallest part of fuel system is described. The optimization of cleaning for the balls before coating was resulted: The best cleaning performance presented the addition of acetone cleaning, water boiling, and then acetone cleaning, confirmed by fluorescence analyzers. The third part of this work was developing low-temperature vacuum carburizing and pre-treatment for parts of injector, stopper (SUS303), and position ring (1.4305) with high wear resistance. The difference between two steels led to the result: high molybdenum of 1.4305 formed Mo-oxides on the surface during acid etching. These Mo-oxides resolved quickly by hydrogen during carburizing and then enabled activated carburizing. The 1.4305 was appropriate for the carburizing and was chosen for stopper.