In order to overcome the tribological issues in friction, wear and adhesion, tribological functional surfaces were fabricated as classified as surface modification, coatings and texturing. In this paper, I explain the control method of friction and adhesion with plasma and fluoride method as surface modification of rubber. Also ultra low friction and low adhesion was happened by friction induced nanometer thickness transformed layer and super hydrohobocity of DLC respectively. And the principles of the improvement of tribological properties with texturing were explained briefly.

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  The friction coefficient can be decreased by increasing the hardness of a sliding plane while maintaining low shear resistance parallel to its substrate using nanostructural control techniques. Herein, nanoperiodic multilayer films composed of solid lubricant materials were proposed to develop a new solid lubricant film having lower friction than that of conventional solid lubricant films. The applied solid lubricant materials were soft metals including Au and Ag, polymers such as PTFE (polytetrafluoroethylene), and crystallizing layered inorganic compounds such as MoS₂ (molybdenum disulfide), WS₂ (tungsten disulfide), graphite, and hexagonal-BN. The nanoindentation properties of the obtained films were evaluated. Multilayered films with a suitable period showed a high hardness and elastic modulus. These nanoperiod multilayer solid lubricant films exhibited lower friction, higher nanowear resistance, and superior friction endurance than those of monolayer films.

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  It is generally taught that low friction and high wear proof of mechanical parts and surfaces are always required. From the commonsense in the world, people already know that we should concern about environmental problems, especially for minimizing the amount of oil use. The carbonaceous thin coating such as Diamond-Like Carbon (DLC) is one of the capable candidates to reduce friction and wear. In this review, we would like to summarize the mechanism of low friction of DLC and CNx, especially for Ali Erdemir, Julian Fontaine and Noritsugu Umehara as strategy of research work. Firstly, the summary of hydrogenated DLC which showed superlow friction by repulsive force is reported. Secondly, the role of hydrogen gas onto low friction of hydrogenated DLC is written. Finally, the superlow friction by CNx and the structural change are summarized.

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  Diamond-like carbon (DLC) films have attractive properties such as low friction, anti-wear, high hardness, and anti-corrosion. Such DLC films have been fabricated with various deposition methods such as magnetron sputtering, ion plating, filtered arc deposition, and plasma-enhanced chemical vapor deposition. The properties such as low friction in vacuum, electrical conductivity, hydrophobicity, and heat resistance can be added to DLC films by the modification of conventional deposition methods, or the doping of foreign elements. These DLC films can be applied to tribological parts in vacuum environment, dies for plastic moldings, inspection components of semiconductors, components of solar cells, and devices of medical engineering. Modified deposition techniques can also fabricate DLC films to large-scale machine components.

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  Molecular simulation approaches to understand the mechanisms of solid lubrication are discussed. Pathway of the solid lubrication is based on surface coating and additives in lubricating oil. Then the formation of transfer layer and the surface modification with chemical reaction come to the topic which should be understood. For the basic understanding, the solid friction model due to lattice vibration is introduced. Then molecular dynamics simulations of boundary water film on the silanol covered surface, formation process of molybdenum disulfide layer, and formation of transfer film of graphene are introduced. Finally the low friction mechanism of graphene transfer layers studied by coarse-grain molecular simulation is discussed.

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  This third lecture of “Basics of Vacuum measurement from viewpoint of Metrology” gives an example to estimate measurement uncertainties based on “Guide to the expression of Uncertainty in Measurement (GUM)” for calibrations of vacuum gauges. Both a capacitance diaphragm gauge (CDG) and a pirani gauge were calibrated by direct comparison to another CDG used as a reference gauge based on JIS Z 8750. Both the procedure to summarize the calibration results and the method to estimate the expanded uncertainty are explained.

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