Abstract: An object of the present invention is to provide a sliding member coated with a DLC coating in which microfractures on the sliding surface thereof due to the progression of cracks are less likely to occur, and in which an increase in abrasive wear can be reduced. The present invention achieves the above-mentioned object by a sliding member having a DLC coating on the outer peripheral surface thereof, wherein an S band derived from sp3 bonding is observed in the DLC coating in addition to a G band derived from the graphite structure and a D band derived from the defects of the graphite structure, and these bands satisfy specific relationships.

Abstract: An object of the present invention is to provide a sliding member coated with a DLC coating in which microfractures on the sliding surface thereof due to the progression of cracks are less likely to occur, and in which an increase in abrasive wear can be reduced. The present invention achieves the above-mentioned object by a sliding member having a DLC coating on the outer peripheral surface thereof, wherein an S band derived from sp3bonding is observed in the DLC coating in addition to a G band derived from the graphite structure and a D band derived from the defects of the graphite structure, and these bands satisfy specific relationships.

Abstract: In this piston ring combination, a second outer peripheral surface, which is the outer peripheral surface of a second ring, has a second protruding surface curved into a convex shape, and a pair of third outer peripheral surfaces, which are the outer peripheral surfaces of a pair of segments, each have a third outer peripheral area in which a third protruding surface is formed, the third protruding surfaces being curved into convex shapes. In at least one of the pair of third outer peripheral surfaces, the peripheral edge on a crank-chamber side is positioned farther outward in the diametrical direction than the peripheral edge on a combustion-chamber side, and a peak of the third protruding surface is positioned nearer to the crank chamber than the center of the third outer peripheral surface.

Abstract: In this piston ring combination, a second outer peripheral surface, which is the outer peripheral surface of a second ring, has a second protruding surface curved into a convex shape, and a pair of third outer peripheral surfaces, which are the outer peripheral surfaces of a pair of segments, each have a third outer peripheral area in which a third protruding surface is formed, the third protruding surfaces being curved into convex shapes. In at least one of the pair of third outer peripheral surfaces, the peripheral edge on a crank-chamber side is positioned farther outward in the diametrical direction than the peripheral edge on a combustion-chamber side, and a peak of the third protruding surface is positioned nearer to the crank chamber than the center of the third outer peripheral surface.

Abstract: To reduce a friction, and to provide an excellent seizing resistance. Provided is a cast iron cylinder liner including an inner peripheral sliding surface made of cast iron, and an internal combustion engine including a cylinder bore including an inner peripheral sliding surface made of cast iron, wherein the inner peripheral sliding surface includes a region satisfying Expression (1) to Expression (3), Rvk/Rk?1.0 ??Expression (1) 0.08 ?m?Rk?0.3 ?m Expression (2) Rk?Rpk>0 Expression (3) [Rk is the core roughness depth based on JIS B0671-2:2002, Rpk is the reduced peak height based on JIS B0671-2:2002, and Rvk is the reduced valley depth based on JIS B0671-2:2002 in Expression (1) to Expression (3)].