A bearing component and a method to form a bearing component. The bearing component comprises a first and a second metallic material wherein the first material presents a first carbon content and the second material presents a second carbon content, wherein the first material and the second material have been joined by a diffusion welding process. The diffusion welding process has resulted in a transition zone with a varying carbon content between the first material and the second material. The varying carbon content in the transition zone is essentially within an interval, wherein the interval end points are defined by the carbon content of the first material and the second material.

A crankshaft with improved fatigue strength is provided. A crankshaft 10 includes journals 11, pins 12, and fillets 14, each fillet 14 having a residual stress distribution where the residual stresses are compressive residual stresses from the surface down to a depth of at least 300 m, the maximum value of the compressive residual stress being not lower than 1000 MPa, the surface roughness Rz being lower than 3.00 m.

A bearing constituent member includes a base material including steel and a carbonitrided layer that is a surface layer on the steel, the steel including 0.3 to 0.45 mass % of carbon, 0.5 mass % or lower of silicon, 0.4 to 1.5 mass % of manganese, 0.3 to 2 mass % of chromium, 0.1 to 0.35 mass % of molybdenum, 0.2 to 0.4 mass % of vanadium, and a remainder of iron and unavoidable impurities. Surface Vickers hardness at a position at a depth of 50 m from a surface of a rolling sliding surface is 700 to 800, internal hardness is 550 to 690 in terms of Vickers hardness, and an amount of residual austenite in a range from the surface to a depth of 10 m is at least 30 vol %.

A pinion bearing arrangement of a gearbox for a vehicle or aircraft, providing at least one roller bearing. At least one of the roller bearings is a ball bearing, having an inner ring and an outer ring, wherein both rings have raceways for balls being located between the rings. To ensure a sufficient lifetime of the roller bearings the invention includes that at least one of the rings is made from a ball bearing steel produced by a powder metallurgical process using a powder metallurgy component including 0.5 to 2.0 weight-% C, a maximum of 0.035 weight-% S, 3.0 to 5.0 weight-% Cr, 1.0 to 4.0 weight-% V, 1.0 to 12.0 weight-% W and 2.0 to 12.0 weight-% Mo, wherein at least one raceway has a radius (r.sub.I/O) and the balls have a diameter (D.sub.B) which fulfill the equation: r.sub.I/O/D.sub.B>0.53.

A retainer (30) for maintaining a relative angular spacing of a plurality of rolling elements includes a body (34) having an annular portion (38) and a plurality of engaging portions (42). Each of the engaging portions is configured to engage at least one of the plurality of rolling elements. The body is made of a sintered powdered metal infiltrated with bronze.

A rolling bearing contains a structure having a solid solution carbon amount in a martensitic structure after heat treatment of 0.35 mass % or more and 0.65 mass % or less and a volume ratio of spheroidized carbides having a diameter of 200 nm or more of 4.5% or less.

A crankshaft with improved fatigue strength and reduced quench cracking is provided. The crankshaft (10) is a crankshaft including a pin (12) and pin tops (15), the pin (12) including a sliding portion (121) having a constant outer diameter, and fillets (122) formed contagiously with the sliding portion (121), each fillet (122) including a hardened region (122a) at its surface, the hardened region being a region with a hardness higher than the hardness of the core of the sliding portion (121) by 100 HV or more, the hardened region (122a) of the fillet (122) having a thickness (d1) not smaller than 12.0% of the radius (R) of the sliding portion (121), the pin tops (15) having a prior-austenite grain size not larger than 60 m.

A bearing component such as a bearing ring includes a metallic base body and at least one alloy steel coating on the base body, the coating being applied to the base body by deposition welding. The base body is preferably non-alloy steel or cast iron, and the alloy includes at least one carbide-forming transition metal such as niobium, tantalum, zirconium, titanium, hafnium, tungsten, molybdenum, vanadium, or manganese. The coating can form a raceway of the bearing component or a structural element such as a flange. Also a method of forming such a bearing component is provided.

There is provided a carburized bearing that is excellent in rolling contact fatigue life with a change in structure under a hydrogen-generating environment. In the carburized bearing, a chemical composition of a core portion consists of, in mass %, C: 0.25 to 0.45%, Si: 0.10 to 0.50 %, Mn: 0.40 to 0.70 %, P: 0.015% or less, S: 0.005% or less, Cr: 0.80 to 1.50%, Mo: 0.17 to 0.30%, V: 0.24 to 0.40%. Al: 0.005 to 0.100%, N: 0.0300% or less, O: 0.0015% or less, and the balance being Fe and impurities, and satisfies Formula (1) to Formula (4) described in the present specification. A proportion of a total area of CaOCaSMgOAl.sub.2O.sub.3 composite oxides with respect to a total area of oxides in the carburized leaping is 30.0% or more, and a number density of oxides having an equivalent circle diameter of 20.0 m or more is 15.0 pieces/mm.sup.2 or less.