A method for manufacturing a bearing ring of a rolling bearing includes a series of steps of cutting out an annular member from a material, forming a surface-hardened layer on the annular member, quenching and tempering the annular member, and polishing inner and outer diameter surfaces of the annular member. The method includes, after the quenching, rapidly cooling the ring member such that the ring member has a surface temperature of 50 C. or lower to form a bearing ring intermediate member, and after the tempering, polishing inner and outer diameter surfaces of the bearing ring intermediate member.

A contact layer is formed by a deposition method on an inner surface of a first metal element by a centrifuging process, and preferably includes an inner layer of copper alloy and an outer layer of tin alloy. Such a contact layer is used in an articulation joint including a first metal element having a surface provided with the contact layer, and a second metal element with a second surface. The first and second elements are relatively movable such that first and second surfaces slide against each other.

A rolling bearing, a rolling device, and a method of manufacturing the rolling device are provided, by which a long life can readily be implemented by suppressing surface damage even on the use condition that the oil film formation performance of a rolling part is poor. A rolling device includes: a first rolling component made of SUJ2; and a second rolling component made of SUJ2 and configured to contact the first rolling component. A surface of a rolling part of the first rolling component is greater in arithmetic mean roughness than a surface of a rolling part of the second rolling component. The arithmetic mean roughness of the surface of the rolling part of the second rolling component is 0.07 m or more and 0.20 m or less.

A bearing part according to one embodiment of the present invention is a bearing part composed of a chromium molybdenum steel, the bearing part including a diffusion layer in a surface of the bearing part. The diffusion layer includes a plurality of compound grains and a plurality of martensite blocks. An average grain size of the compound grains is less than or equal to 0.3 m. An area ratio of the compound grains in the diffusion layer is more than or equal to 3%. A maximum grain size of the plurality of martensite blocks is less than or equal to 3.8 m.

An outer ring includes an outer ring small-diameter part extending toward one axial side with respect to the outer ring raceway, a radial wall part extending from an axial end portion of the outer ring small-diameter part toward an inner diameter-side, and a folded-back part extending from a radially inner end portion of the radial wall part toward the other axial side. The folded-back part radially overlaps the inner ring small-diameter part with a radial gap therebetween. The radial gap of an inner diameter-side entry formed by an axial end of the folded-back part and the inner peripheral surface of the inner ring small-diameter part is smaller than the radial gap of an inner diameter-side exit formed by an axial end of the inner ring small-diameter part and an outer peripheral surface of the folded-back part.

An annular ring having a contact portion, a raceway and a squirrel-type cage secured to the contact portion. The contact portion is formed from a first metal material, and the squirrel cage is formed from a second composite-type material including a matrix in which reinforcing fibres are embedded, the pierced portion of the squirrel cage being attached to an outer surface of the contact portion. Also, a bearing assembly with rolling elements having an outer ring, an inner ring coaxial with the outer ring, and a plurality of rolling elements housed between the raceway of the contact portion of the outer ring and a raceway of the inner ring.

A connection element providing a first ring and a second ring, the two rings rotating relative to one another about a central axis, the first ring having a contact portion with a contact surface interacting with the second ring for the relative rotation, and a fastening portion configured to be rigidly secured to a support. The contact portion is made of a first material and the fastening portion is made of a second material, different to the first material, the first material having a hardness strictly greater than that of the second material, and the second material having a structural fatigue strength strictly greater than that of the first material.

The steel material for a carburized bearing part according to the present invention contains, by mass %, C: 0.25 to 0.45%, Si: 0.15 to 0.45%, Mn: 0.40 to 1.50%, P: 0.015% or less, S: 0.005% or less, Cr: 0.60 to 2.00%, Mo: 0.10 to 0.35%, V: 0.20 to 0.40%, Al: 0.005 to 0.100%, Ca: 0.0002 to 0.0010%, N: 0.0300% or less and O: 0.0015% or less, with the balance being Fe and impurities, and satisfies Formulae (1) to (3).

1.20<0.4Cr+0.4Mo+4.5V<2.75(1)

A1/A2>0.50(2)

2.7C+0.4Si+Mn+0.45Ni+0.8Cr+Mo+V>2.55(3)

Formula (2) shows an area fraction of sulfides containing Ca in an amount of 1 mol % or more among sulfides having an equivalent circular diameter of 1 m or more.

A production method produces a precision rail having a raceway region. The material for producing at least one part of the raceway region is deposited onto a component by laser beam build-up welding and/or electron beam build-up welding. The methods results in short processing times being achieved when the precision rails concerned are produced.

A method of manufacturing a slide of a variable oil pump for a vehicle includes preparing a molded body for a slide of a variable oil pump using prealloy powder including, in percent (%) by weight of the entire composition, 0.45 to 0.55% of carbon (C), 2.8 to 3.2% of chromium (Cr), 0.45 to 0.55% of molybdenum (Mo), 0.35 to 0.5% of manganese (Mn), 0.1 to 0.25% of sulfur (S), and the remainder of iron (Fe) and inevitable impurities. A sintered body is prepared by sintering the molded body. The sintered body is slowly cooled such that a temperature of the sintered body reaches a first temperature range and rapidly cooled when the first temperature range is reached.