A tapered roller bearing includes an inner ring having a tapered raceway surface and a large-collar surface on a large-diameter side of the raceway surface, and tapered rollers. Each of the rollers has a large end surface guided by the large-collar surface. When R represents a set curvature radius of the large end surface and R.sub.BASE represents a base curvature radius from a vertex of a cone angle of each of the tapered rollers to the large-collar surface, the base curvature radius R.sub.BASE is 100 mm or less, and a ratio R/R.sub.BASE of the set curvature radius R to the base curvature radius R.sub.BASE is set to 0.90 or less. When R.sub.ACTUAL represents an actual curvature radius of the large end surface of each of the tapered rollers, a ratio R.sub.ACTUAL/R of the actual curvature radius R.sub.ACTUAL to the set curvature radius R exceeds 0.5.

Apparatus and methods for achieving a high strength bonded joint between a stub connector and a shaft.

To provide a hub bearing that is capable of reducing a delay in a response of the hub bearing and improving a steering stability of a vehicle. A hub bearing 1 includes an outer ring 2 serving as a stationary side raceway ring, a hub wheel 3 and an inner ring 5 serving as a rotatable side raceway ring, balls 4 serving as a plurality of rolling elements disposed between a raceway surface of the stationary side raceway ring and a raceway surface of the rotatable side raceway ring, and grease that lubricates a rolling contact part between each of the raceway surfaces and the rolling elements. The surface roughness of at least one raceway surface selected from the raceway surface of the stationary side raceway ring and the raceway surface of the rotatable side raceway ring in the rolling contact part is 0.03 μmRa or less. Further, the grease has a traction coefficient in the rolling contact part of 0.04 or less at 40° C. when a vehicle speed is 20 km/h or more.

Provided are sliding components capable of obtaining a stable low-friction effect under a wide range of conditions of use. A sliding component has a relatively sliding surface. A base material of one of the sliding components is coated with a graphite film, and the sliding surface of the other of the sliding components is made of the graphite film.

Provided is a friction design method capable of estimating sliding friction generated between mutual sliding surfaces of two sliding members lubricated with lubricant with high precision. The friction design method sets a friction coefficient μ in a sliding surface model corresponding to mutual sliding surfaces of two sliding members (2 and 3) lubricated with lubricant (step S1), and, based on a correlation between the friction coefficient μ and an oil film parameter (Λ(Rk) or Λ(Rk+Rpk)) calculated using a core portion level difference (Rk) or a sum of the core portion level difference (Rk) and reduced peak height (Rpk) as a parameter representing surface roughness in the sliding surface model (step S2), sets a target value for surface roughness of the sliding surfaces required to be controlled as a product (steps S3 to S6).

Wettable structures that retain liquid layers are defined at surfaces of substrates. The wettable structures include grooves or ridges that are spaced apart by between 10 nm and 10 μm and can be defined in substrate or in a layer formed on a surface of the substrate. In typical examples, wettable structures are defined with hydrophobic materials or at hydrophobic surfaces and produce hydrophilic surfaces.

A sliding member includes an overlay layer made of a resin on a side of a sliding surface of a bearing alloy layer. When a valley void volume Vvv (μm.sup.3/μm.sup.2) in the sliding surface of the overlay layer is defined as Vv1, Vv1 is in a range of 0.015≤Vv1≤0.200.

An apparatus is provided that includes a diamond bearing surface positioned in sliding engagement with an opposing bearing surface of a diamond reactive material. The opposing bearing surface is hardened via a material treatment.

A sliding material including: a substrate, and a textured sliding layer overlying the substrate, where the sliding layer includes asperities including a plurality of apexes and nadirs, where 1) the sliding layer has a root mean square gradient of less than 0.064; 2) the sliding layer has an apex material portion of less than 10%; 3) the sliding layer has a nadir material portion of less than 75%, and where the textured sliding layer induces formation of a film when engaged in a rotational interface w/ another component.

A sliding member includes a resin overlay layer on a sliding surface side coming into sliding contact with a mating member. The resin overlay layer has a surface roughness parameter Rk satisfying 0.4≤Rk≤1.2, and a surface area ratio S=S2/S1 calculated when an area of an arbitrary measurement field of view is designated by S1 and a surface area of the measurement field of view is designated by S2 satisfies 2.5≤S≤4.5.