Abstract: A rolling bearing in which at least one of the bearing rings is obtained by applying a induction heat treatment to a spheroidizing annealed steel material having a DI value of 1.0 or more to form a hardened layer having a hardness of 550 HV or more on at least a raceway surface and a fitting surface. In the induction heat-treated bearing ring, (A) an average retained austenite amount is 12 vol % or less, (B) the raceway surface has a retained austenite amount of 12 vol % or more and a residual compressive stress of ?100 MPa or less, and (C) a difference between a hardness of the raceway surface and a minimum hardness of a region having a hardness of less than 550 HV is 150 HV or more.

Abstract: A method for manufacturing a rolling-element bearing includes forming an inner ring from a steel having a sulfur content of 0.002 to 0.015 mass % and an oxygen content of less than 15 ppm, subjecting the inner ring to a hardening heat treatment that ends by performing a final heat treatment step at a predetermined temperature, cold working the inner-ring raceway to generate compressive residual stresses at least in a surface layer of the inner-ring raceway, subjecting the inner ring to a bluing treatment and subjecting the blued inner ring to a thermal post-treatment process at a temperature below the predetermined temperature of the final hardening heat treatment step. The resulting rolling-element bearing may exhibit compressive residual stresses having an absolute value of at least 200 MPa at 0.1 mm beneath the outer surface of the inner-ring raceway and a maximum value of 1500 MPa or less throughout the inner ring.

Abstract: A method of manufacturing a lift transmitting component (2), particularly for a gas exchange valve train or a fuel pump drive of an internal combustion engine (1), is provided, The lift transmitting component includes a housing (6), a bearing pin (7) fixed in a reception bore (9) of the housing (6) and a roller (8) mounted through a sliding or a rolling bearing on the bearing pin (7). The bearing pin is core-hardened over an entire axial length to a core hardness of at least 650 HV, and pin ends (10) of the core-hardened bearing pin are radially widened relative to the reception bore for enabling a connection of the bearing pin to the housing (6) through positive engagement. The hardness of the bearing pin is at the most 780 HV, the radial widening of one of the pin ends being realized with a shaping die (11) which travels axially parallel to the bearing pin (7) and applies a force to the pin end in a transition region between a periphery and a front end surface of the bearing pin.

Abstract: A bearing component formed from a bearing steel, wherein the component has an outer surface and comprises through-hardened bainite and/or martensite and has a substantially homogeneous chemical composition, at least a part of the bearing component having a compressive residual stress profile comprising ?25 to ?1000 MPa at the near surface, wherein the near surface is defined as a region 500 microns or less below the outer surface.

Abstract: An outer ring and an inner ring of a rolling bearing are constituted of steel containing 0.77 to 0.85% of carbon, 0.01 to 0.25% of silicon, 0.01 to 0.35% of manganese, 0.01 to 0.15% of nickel, 3.75 to 4.25% of chromium, 4 to 4.5% of molybdenum and 0.9 to 1.1% of vanadium with the rest consisting of iron and impurities, a nitrogen-enriched layer having a nitrogen concentration of at least 0.05 mass % is formed on a region including a rolling surface, and the total of a carbon concentration and the nitrogen concentration in the nitrogen-enriched layer is at least 0.82 mass % and not more than 1.9 mass %. A DLC coating layer is arranged on a region including an outer ring contact surface.

Abstract: An outer ring, an inner ring and a ball serving as mechanical components configuring a deep groove ball bearing are formed of steel containing at least 0.77 mass % and not more than 0.85 mass % of carbon, at least 0.01 mass % and not more than 0.25 mass % of silicon, at least 0.01 mass % and not more than 0.35 mass % of manganese, at least 0.01 mass % and not more than 0.15 mass % of nickel, at least 3.75 mass % and not more than 4.25 mass % of chromium, at least 4 mass % and not more than 4.5 mass % of molybdenum and at least 0.9 mass % and not more than 1.1 mass % of vanadium with a remainder consisting of iron and impurity, and have raceway/rolling contact surfaces, the surface being included in a region having a nitrogen enriched layer having a nitrogen concentration of at least 0.05 mass %, the nitrogen enriched layer having a carbon concentration and the nitrogen concentration, in total, of at least 0.82 mass % and not more than 1.9 mass %.

Abstract: Disclosed is a ball for a constant velocity joint, and a method for producing the same. The ball for a constant velocity joint is produced via a quenching step for heating a spherical body consisting of a material corresponding to a high carbon chromium bearing steel regulated by Japanese Industrial Standards (JIS) to 840-900° C. and then cooling the spherical body under such a condition as 10-25 vol. % of austenite remains up to a first part where the depth from the surface is 0.1 mm, a step for tempering the spherical body at 150° C. or more, and a step for shot peening the spherical body and imparting a compression residual stress of ?1000 MPa or more to a region reaching second part where the depth from the surface is 0.2 mm.

Abstract: A steel part having a long rolling contact fatigue life and capable of further increasing the life of a bearing under severer using condition than usual conditions. The steel part includes steel having a composition containing 0.7% by mass to 1.1% by mass of C, 0.5% by mass to 2.0% by mass of Si, 0.4% by mass to 2.5% by mass of Mn, 1.6% by mass to 5.0% by mass of Cr, 0.1% by mass to less than 0.5% by mass of Mo, 0.010% by mass to 0.050% by mass of Al, less than 0.0015% by mass of Sb as an impurity, and the balance composed of Fe and inevitable impurities, the steel being hardened and tempered. In the steel structure of a portion from the surface to a depth of 5 mm, residual cementite has a grain diameter of 0.05 to 1.5 ?m, prior austenite has a grain diameter of 30 ?m or less, and the ratio by volume of the residual austenite is less than 25%.

Abstract: A rolling apparatus including an external member having a raceway surface on an inner peripheral surface thereof, an internal member having a raceway surface on an outer peripheral surface thereof, and a plurality of rolling elements which are rotatably provided between the raceway surface of the external member and the raceway surface of the internal member. A surface of at least one of the internal member, the external member, and the rolling elements is subjected to carbonitriding or nitriding; an area percentage of a nitride containing Si and Mn is 1% or more and 20% or less; surface hardness is HV750 or more. When depth from the raceway surface or depth from a rolling surface of the rolling element is defined as Z and diameter of the rolling element is defined as d, hardness at Z=0.045 d is HV650 to 850, and hardness at Z=0.18 d is HV400 to 800.

Abstract: A rolling bearing comprises an outer ring, an inner ring and rolling elements rotatably disposed between the outer and inner rings. At least a member selected from the outer ring, inner ring and rolling elements has C content of 0.2 or more and 0.6 or less wt %, Cr content of 2.5 or more and 7.0 or less wt %, Mn content of 0.5 or more and 2.0 or less wt %, Si content of 0.1 wt % or more and 1.5 or less wt %, and Mo content of 0.5 or more and 3.0 or less wt %. Further, a carburizing or carbo-nitriding treatment, a quenching treatment and a tempering treatment are applied to the selected member. Furthermore, retained austenite on a surface thereof is 15% or more and 45% or less vol. %, and the surface hardness thereof is HRC60 or more.

Abstract: A sintered sliding member comprises a back metal (21a) and a ferrous sintered sliding body (20) which is sintering-bonded to the back metal (21a). The ferrous sintered sliding body (20) has martensite phase having a solid soluble carbon concentration of 0.15 to 0.5 wt % and contains carbide in a content of 5 to 50% by volume. The sintered sliding member is excellent in abrasion resistance, seizing resistance and heat crack resistance.

Abstract: An alloy for aircraft roller bearings containing: 0.45 to 1.0 wt. % carbon, max 2.0 wt. % manganese, max 1.0 wt. % silicon, 8.5 to 11.5 wt. % chromium, 1.0 to 4.5 wt. % molybdenum, 1.0 to 2.5 wt. % vanadium, max 2.0 wt. % tungsten, max 0.5 wt. % niobium, max 0.5 wt. % tantalum, max 3.0 wt. % nickel, max 0.5 wt. % cobalt, max 0.1 wt. % aluminum, max 0.01 wt. % nitrogen, and the balance being iron and impurities due to production.

Abstract: Provided are a steel having excellent rolling contact fatigue life and the manufacturing method thereof. The steel consists essentially of 0.7 to 1.1% C, 0.2 to 2.0% Si, 0.4 to 2.5% Mn, 1.6 to 4.0% Cr, 0.1% or more and less than 0.5% Mo, 0.010 to 0.050% Al, bymass, and balance of Fe and inevitable impurities, is treated by quenching and tempering, has residual cementite grain sizes ranging from 0.05 to 1.5 ?m, and has prior-austenite grain sizes of 30 ?m or smaller. When the steel is used to bearing steel, the bearing life extends even under service in more severe environments.

Abstract: A bearing for alternators and a bearing for pulleys for reducing hydrogen embrittlement or cracking is used when the bearing is in an environment having a severe condition, such as, when hydrogen is generated from grease or the like. The bearing includes a rolling element, an inner ring and an outer ring, and at least one of the rolling element, where the inner and outer rings have a nitrogen enriched layer containing austenite crystal grains having a grain size number exceeding 10.

Abstract: There is provided an inexpensive rolling element used under high interface pressure such as induction hardened gears, the rolling element being improved in the seizure resistance of its tooth flanks and having a temper hardness of HRC 50 or more at 300° C. To this end, the rolling element is made from a steel material containing at least 0.45 to 1.5 wt % C and one or more alloy elements selected from 0.1 to 0.5 wt % V and 0.3 to 1.5 wt % Cr, and has a rolling contact surface layer having a structure tempered at low temperature in which 2 to 18% by volume cementite disperses in a martensite parent phase formed by induction heating and cooling and containing 0.25 to 0.8 wt % carbon solid-dissolving therein.

Abstract: Various inexpensive rolling elements for use under high interface pressure such as induction hardened gears are provided, which have improved seizure resistance at tooth flanks and a temper hardness of HRC 50 or more at 300 ° C. To this end, a rolling element is made from a steel material which contains at least 0.5 to 1.5 wt % carbon and 0.2 to 2.0 wt % one or more alloy elements selected from V, Ti, Zr, Nb, Ta and Hf; and in which 0.4 to 4.0% by volume one or more compounds selected from the carbides, nitrides and carbonitrides of the above alloy elements and having an average particle diameter of 0.2 to 5 ?m are dispersed. In such a rolling element, the soluble carbon concentration of a martensite parent phase of a rolling contact surface layer is adjusted to 0.3 to 0.8 wt %, the martensite parent phase having been subjected to induction hardening and low temperature tempering, and one or more of the above carbides, nitrides and carbonitrides are dispersed in an amount of 0.4 to 4.

Abstract: A constant velocity universal joint includes an inner race having an outer peripheral face on which inner grooves are formed, an outer race having an inner peripheral face on which outer grooves are formed, a plurality of balls each engaging with each pair of inner groove and outer groove, and an annular cage disposed between the inner race and the outer race and including window portions for retaining respective balls. A coefficient of sliding friction between the ball and a rolling face on the inner groove with which the ball is in contact, and a coefficient of sliding friction between the ball and a rolling face on the outer groove with which the ball is in contact are larger than a coefficient of sliding friction between the ball and a sliding face on the window portion with which the ball is in contact.

Abstract: An inner ring 2 and an outer ring 3 of a rolling bearing 1 are made from steel that contains carbon in the range of 0.65 to 1.25% by mass, silicon in the range of 0.7 to 2.5% by mass, manganese in the range of 0.1 to 1.5% by mass, chromium in the range of 0.5 to 3.0% by mass, 1.5% by mass or less of molybdenum, 9 ppm or less of oxygen, 30 ppm or less of titanium, and 80 ppm or less of sulfur, and whose rating number of the Thin type A series inclusion is 1.5 or less and that of the Heavy type A series inclusion is 1.0 or less when the rating numbers are measured by a method stipulated in ASTM E45.

Abstract: There is provided an inexpensive rolling element used under high interface pressure such as induction hardened gears, the rolling element being improved in the seizure resistance of its tooth flanks and having a temper hardness of HRC 50 or more at 300° C. To this end, the rolling element is made from a steel material containing at least 0.45 to 1.5 wt % C and one or more alloy elements selected from 0.1 to 0.5 wt % V and 0.3 to 1.5 wt % Cr, and has a rolling contact surface layer having a structure tempered at low temperature in which 2 to 18% by volume cementite disperses in a martensite parent phase formed by induction heating and cooling and containing 0.25 to 0.8 wt % carbon solid-dissolving therein.

Abstract: A case hardening bearing steel having an excellent rolling contact fatigue life in intermediate temperature, in addition, excellent toughness at room temperature is provided. Specific means for solving the problems are as follows. The composition contains, by mass percent, C of 0.15 to 0.30 mass percent, Si of 0.5 to 2.0 mass percent, Mn of 0.3 to 2.0 mass percent, Cr of 1.3 to 2.5 mass percent, Mo of 0.3 to 1.0 mass percent, and O of not more than 0.0012 mass percent in a range where (Si+Mo)?1.0 mass percent is satisfied, and contains iron and inevitable impurities as remnant; the maximum size of oxide nonmetallic inclusion is not more than 12.5 ?m when examined area is 320 mm2; number of the oxide nonmetallic inclusion having a diameter of equivalent circle of 3 ?m or more is not more than 250 when the examined area is 320 mm2; in addition, C density of an outer layer is adjusted to be in a range from 0.7 to 1.2 mass percent by carburization.

Abstract: A roller member comprising high carbon chromium bearing steel having a carburization treatment. The bearing steel comprising a surface portion defined as a range between a surface of a rolling face of the roller member to a depth where a maximum shearing stress acts thereon, the surface portion containing carbon in a total amount comprising a range of 1.0 to 1.6 wt % and an amount of residual austenite comprising a range of 20 vol % to 35 vol % wherein a compression residual stress of the surface portion comprises a range of 150 to 1000 MPa, wherein a surface hardness of the surface portion comprises a range of 64 or higher in Rockwell C hardness, wherein an amount of carbide precipitate on the surface portion comprises a range of 10% to 25% in an area rate and each carbide particle size comprises a range of 3 ?m or less.

Abstract: A rolling bearing for belt-type continuously variable transmission with a metal belt including pieces has an inner ring; an outer ring; and rolling elements, wherein at least one of the inner ring, the outer ring and the rolling element is made of an iron alloy having a chromium content of from 2.5 to 20.0% by weight.

Abstract: A process for producing a component of metal includes a) carrying out a heat treatment to harden the component, which ends with a heating process, especially with a tempering or microstructural transformation process, at a given temperature (TE); b) carrying out at least machining of the component at room temperature (TU) in order to provide its desired geometrical shape; and c) subsequent heating of the component to a temperature (T) which is greater than room temperature (TU).

Abstract: A cylindrical roller bearing or needle roller bearing for use with a rolling raceway surface is subjected to a carbonitriding treatment to produce a layer containing 30 to 80% retained austenite in the vicinity of its surface that contacts a carburized layer of a rolling raceway surface of a roller bearing. The amount of retained austenite of the surface layer of the roller bearing is increased by about 30%. The surface layer is then heat treated to apply a residual compression stress. The surface then receives surface finishing to produce micro concavo-convex portions in a random direction.

Abstract: A rolling bearing including a rolling element made of steel is provided. The rolling element has a hardness of 620 to 750 HV in its interior. The rolling element is so constructed that the hardest point may exist within a depth of 10% of its diameter from a rolling contact surface of the rolling element, and that the hardness at this point is made higher by 20 to 150 HV than the hardness in the interior.

Abstract: Method for the production of a part of a rolling bearing, such as a ring for a ball bearing. The starting material used is a grade of steel containing 0.90 1.00% C; at most 0.15% Si; 0.25-0.45% Mn; at most 0.0015% P; at most 0.010% S; 1.30-1.50% Cr; at most 0.15% Ni; 0.20-0.23% Mo; at most 0.20-0.23% Cu; at most 20 ppm Ti; at most 8 ppm O. Before subjecting this grade of steel to a quenching and tempering treatment, the shaped item is subjected to plastic deformation in the hot or cold state. The mechanical properties and in particular the anticipated life under severe stress improve as a result.

Abstract: The present invention provides a rolling bearing having high wear resistance at high temperature and with reduced manufacturing cost. At least one of an inner ring, an outer ring and rolling elements is formed of the following steel material into a predetermined shape, then applied with hardening and tempering at a temperature of 240° C. or higher or 350° C. or lower to make the Vickers hardness (Hv) on the raceway surface and/or rolling surface to 720 or more. The steel material contains, as the alloy ingredient, 0.8% by weight or more and 1.2% by weight or less of C, 0.5% by weight or more and 2.5% by weight or less of Si, 0.7% by weight or more and 1.5% by weight or less of Cr, 0.8% by weight or more and 2.0% by weight or less of Mo and 0.3% by weight or more and 1.2% by weight or less of Mn, with a ratio of Mo to Cr (Mo/Cr: weight ratio) of 1.1 or more.

Abstract: A surface to serve as a surface under ultrasonic inspection has a roughness of 0.4 &mgr;mRa or less, and wherein all imperfections existing a controlled volume X corresponding to all cross sections of a raceway ring 1 assume a length of 0.2 mm or less as represented by the square root of areas of the imperfections. Accordingly, it is possible to provide a rolling bearing which does not become short-lived and obviates a concern about occurrence of cracking even when used in a harsh environment.

Abstract: There are provided a rolling bearing comprising an outer race, an inner race, and a plurality of rolling elements each interposed between the outer race and the inner race, at least one of the outer race, the inner race and the rolling elements being made of a steel consisting essentially, by mass, of 0.40 to 0.60% C, not more than 0.5% Si, not more than 0.5% Mn, not less than 8.0% but less than 10.0% Cr, and the balance Fe and incidental impurities, said steel having a hardness not less than 740 HV, carbides contained in said steel having a long size not more than 1.2 &mgr;m, and an amount of said carbides being not more than 3.5% in area %, and a method of producing the rolling bearing.

Abstract: There can be obtained a rolling part and power transmission part excluding any expensive elements as its constituents and formed of inexpensive elements C, Si and Mn optimized to allow the same to have a long rolling life under severe conditions for use and be inexpensive and excellent in workability. It is formed of steel shaped and thus processed, and containing 0.5 to 0.7% by weight of C, 0.6 to 1.2% by weight of Si and 0.6 to 1.0% by weight of Mn, as represented in percentage, to satisfy: L≧5000  (1), wherein L=11271 (C wt %)+5796 (Si wt %)+2665 (Mn wt %)−6955; and 23≦H≦25  (2), wherein H=48.0 (C wt %)+5.7 (Si wt %)+11.5 (Mn wt %)−16.2.

Abstract: An outer ring 2 as a stationary ring is fabricated with an iron-steel material of the following composition. Alloying components contain carbon (C) 0.40 wt % to 1.20 wt %, silicon (Si) and/or aluminum (Al) 0.7 wt % to 2.0 wt %, manganese (Mn) 0.2 wt % to 2.0 wt %, nickel (Ni) 0.1 wt % to 3.0 wt % and chromium (Cr) 3.0 wt % to 9.0 wt %. Cr-equivalent amount shown in the following (1) formula is 9.0 wt % to 17.0 wt %. In the bearing face, the hardness is HRC57 or higher, fine carbides (diameter 50 to 500 nm) are dispersively precipitated, and the maximum diameter of carbide is less than 10 &mgr;m. Cr-equivalent amount (%)=[Cr]+2[Si]+1.5[Mo]+5[V]+5.5[Al]+1.75[Nb]+1.5[Ti]  (1).

Abstract: A rolling bearing having excellent corrosion resistance and having a long life for use in airplanes is provided. The constituent parts of the rolling bearing are made from an alloy steel containing Cr which is required for the improvement of a rolling contact fatigue life at a high temperature and is most effective for providing steels with corrosion resistance when 7.0% or more to 16% or less on a weight percent basis is provided. The amount of a residual austenite on the surface of the completed product is from 6% or more and, preferably, 35% or less by stabilizing the residual austenite.

Abstract: A plain bearing for necks of rolls of rolling mills includes a bearing bushing of metal and a plain bearing alloy introduced into the bushing. The plain bearing alloy is based on tin with antimony and copper and contains of 6.8 to 7.2 percent by weight antimony, 6.3 to 6.7 percent by weight copper, 0.5 to 0.7 percent by weight zinc, 0.05 to 0.15 percent by weight silver, and tin as the remainder, and wherein the plain bearing alloy is applied to an inner mantle of a pre-heated bearing bushing as a rough layer thickness of 4 to 5 mm by centrifugal casting.

Abstract: A method of performing a heat treatment on steel rings, in particular for bearings, whereby the outer surface and inner surface of a preheated ring are exposed to different flows of a cooling medium such that the regions of the ring adjacent those surfaces are subjected to different cooling processes. The flow supply of the cooling medium is controlled in such a way that a desired internal stress pattern is obtained in the ring. The cooling medium includes of a combination of liquid and gas. An apparatus for performing a heat treatment on steel rings includes a support means for a ring to be treated; first and second supply means for supplying a spray or mist of a liquid, gas or combination thereof to the outer surface or inner surface of the ring, control means for controlling the supply of the spray or mist is also disclosed.

Abstract: A steel for a large bearing suitable for parts of a large-sized bearing which are excellent in resistance to breakage and rolling fatigue life characteristics, and having a chemical composition by mass percentage of 0.80 to 1.30% of C, more than 0.35% and not more than 0.80% of Si, 0.30 to 0.90% of Mn, 0.90 to 1.50% of Cr, one or both of not more than 0.25% of Mo and 0.20 to 1.50% of Ni, the remainder being Fe and inevitable impurities, and exhibiting the following quench-hardenability measured according to a method specified in JIS G 0561: a HRC of 64 or more at J 1.5 mm, a HRC of 63 to 66 at J 7 mm, a HRC of 37 to 50 at J 15 mm, a HRC of 30 to 45 at J 20 mm, a HRC of 28 to 38 at J 45 mm.

Abstract: A ball for use in a constant-velocity joint, which is adapted to be interposed between an inner race and an outer race for transmitting rotational power therebetween, is produced by nitriding a surface of a ball made of bearing steel or a material equivalent thereto, and processing the nitrided ball for increased resistance to a crushing load. The nitrided ball is processed for increased resistance to a crushing load by tempering the ball at a temperature ranging from 180 to 230° C. The surface hardness of the ball should preferably be adjusted in the range from HRC 60 to 64.

Abstract: A rolling bearing includes races and rolling elements, at least the race including: 0.60 wt % to 0.95 wt % of C; 10.0 wt % to 13.0 wt % of Cr; and at least one kind of 0.5 wt % to 2.0 wt % of Mo and 0.5 wt % to 2.0 wt % of V with the balance of Fe. The surface hardness of a raceway surface of the race is not less than HRC 58, and the raceway surface of the race has a passive film with the thickness of 5 to 100 nm.

Abstract: Machine part is constituted with steel with the carbon content of 0.2% or more and reduced with the hydrogen content after hardening by a heat treatment to 0.04 ppm or less. Further, hardness after hardening by the heat treatment is made to Hv 450 or more.

Abstract: Rolling structure steel, comprising: 0.90-100% by wt. C; 0.95-1.05% by wt Si; 0.25-0.45% by wt Mn; 0.015% by wt. S max.; 0.025% by wt. P max.; 1.30-1.50% by wt. Cr, and 0.17-0.20% by wt. Mo. Preferably this steel is produced by austenising at 860+20° C., quenched in oil and tempered at 240+20° C. In this way steel is obtained having a high rolling contact fatigue strength and dimensional stability at elevated temperature operating conditions.

Abstract: An antifriction bearing comprises bearing rings and rolling members which are made from a steel material containing 0.15 to 0.3 wt. % of carbon by being subjected to heat treatments including carburizing. The surface layer of raceway surface of each of the bearing rings and the surface layer of rolling surface of each of the rolling members are 1.0 to 1.5 wt. % in carbon content, 64 to 66 in Rockwell hardness C, 150 to 2000 MPa in compressive residual stress, up to 3 &mgr;m in maximum carbide particle size and 10 to 25% in carbide area ratio, at a depth of 0 to 50 &mgr;m as measured from the outermost surface of the surface layer. The surface layers are 0.75 to 1.3 wt. % in carbon content, 150 to 1000 MPa in compressive residual stress, 25 to 45% in residual austenite content, up to 1 &mgr;m in maximum carbide particle size and up to 15% in carbide area ratio, at a depth of 50 to 200 &mgr;m as similarly measured from the outermost surface.

Abstract: A rolling bearing including a rolling element made of steel is provided. The rolling element has a hardness of 620 to 750 HV in its interior. The rolling element is so constructed that the hardest point may exist within a depth of 10% of its diameter from a rolling contact surface of the rolling element, and that the hardness at this point is made higher by 20 to 150 HV than the hardness in the interior.

Abstract: An outer ring 2 as a stationary ring is fabricated with a steel material having the composition as shown under. The steel material contains, as alloying elements, C 0.80 to 1.10 wt %, Si 0.20 to 0.50 wt %, Mn 0.2 to 1.0 wt %. It also contains any two kinds or more of Cr, Mo and V at rates of Cr: 1.2 to 3.5 wt %, Mo: 0.5 to 1.5 wt % and V: 0.2 to 1.0 wt %. The containing rates of Cr, Mo and V satisfy the under mentioned formula (1). It further contains Ti and/or Cu at rates of Ti: 0.05 to 0.20 wt % and Cu: 0.2 to 2.0 wt % 1.8≦[Cr]×0.6+[Mo]×0.5+[V]≦3.0  (1). Accordingly, it is possible to remarkably lengthen the life of a rolling bearing such as a bearing for alternator to be used under high vibration and high load.

Abstract: A bearing and a method for fabricating a bearing. The bearing is intended to be used in office automation equipment and the like is improved in impact resistance and load capacity. Its rotational accuracy will not deteriorate in long-term use and its quietness can be maintained over a long period of time. The bearing is an anti-friction bearing located between portions supporting a load and in relative motion to each other. The anti-friction bearing has an outer ring of 30 mm or less in diameter, in which high carbon chromium bearing steel constituting the anti-friction bearing includes the following compositions: C of 0.90-1.30 wt %, Si of 0.40-1.20 wt %, Mn of 0.90-1.0 wt %, and Cr of 0.90-1.70 wt %. After quenching, the tempering temperature used for this bearing is maintained in the range of 170° C. and 250° C. so that the amount of retained austenite in the surface layer after heat treatment is stabilized at 6 by volume or less.

Abstract: A wheel bearing unit is provided in which the service life level is improved without making the size and weight of the bearing unduly large. The wheel bearing unit for rotatably supporting a car wheel on the body of a motor vehicle comprises a rotary member, an outer ring, and double rows of rolling elements. The rotary member comprises a hub wheel to which a car wheel is attached and an inner ring press-fitted to the outer circumference of the smaller end face of the hub wheel, wherein double rows of raceway surfaces are formed in the outer circumferential surfaces of the hub wheel and the inner ring, respectively. The outer ring has double rows of raceway surfaces formed therein so as to be opposite to the raceway surfaces of the hub wheel and the inner ring, and is fixedly coupled to a car-body-side knuckle. The double rows of rolling elements are interposed between the raceway surfaces of the hub wheel, the inner ring, and the outer ring.

Abstract: A method for producing a rolling bearing component, in which, before ustenizing, the steel is subjected to cold deformation and quenching is such that the bainitic structure is obtained; and a rolling bearing component produced by the method, such as a rolling bearing ring from 1C to 1,5Cr type series steel, in which at least the surface of the rolling bearing component has a bainitic structure and the service life of the bainitic structure is considerably increased over a component not subjected to cold rolling.

Abstract: An inner ring and an outer ring are composed as follows. These members are fabricated with a steel for bearing containing carbon 0.6 wt % or higher. A carbonitrided layer is formed in a raceway surface. The amount of residual austenite at a position of 2% Da depth in the raceway surface is determined to be 1.0 vol % or lower. Hardness at the position of 2% Da depth is set to be HRC58 or more. Nitrogen content (Np) at the position of 2% Da depth is 0.05 wt % or more. A multiple Gd of an impression resistance expressed with the following formula (1) is 1.6 or more, Gd=(H0.2/500)+2·Np  (1), wherein in the formula, H0.2 is meant by Vickers hardness at the position of 2% Da depth.

Abstract: In a toroidal-type continuously variable transmission, at least one of components including inner and outer races of a power roller bearing, an input disk, and an output disk is composed of an alloy steel material containing C: 0.15 to 0.5 wt %, Si: 0.1 to 1.5 wt %, Mn: 0.1 to 1.5 wt %, Cr: 0.5 to 3.0 wt %, and at least one kind selected from Mo: 0.1 to 3.0 wt % and V: 0.1 to 3.0 wt %, a content of 0 in the alloy steel material being set to be not more than 9 ppm; and the surface of the at least one component after carbonitriding, hardening and tempering treatments is set to contain C: 0.8 to 1.2 wt % and N: 0.05 to 0.20 wt %, and the at least one component has surface hardness of Hv 720 or more, and Mo.V carbide/carbonitride, the average particle size of which is in a range of from 50 nm to 500 nm is dispersed and precipitated on a race surface or in a range of from the race surface to a deep position where a maximum shearing stress is generated.

Abstract: A process for forming a roller bearing comprising the steps of providing a cylindrical slug that comprises at least 0.7 weight percent carbon and up to 1.6 weight percent of at least one alloying element. The slug has lateral and side surfaces. A centered indentation is formed in each side surface. A circular chamfer surface is formed at the intersection of each side and each lateral surface, thereby producing an upsetting slug. The upsetting slug is cold formed, thereby deepening the centered indentations and forming a blank. The blank has a web separating the deepened indentations and end surfaces and chamfer surfaces that are substantially at net shape for the roller bearing. The web is removed from the blank, thereby forming a pierced blank having a through hole with an inner surface. The inner and lateral surfaces of the pierced blank are finished to the specified inner and outer diameters for the roller bearing.

Abstract: In a balling bearing 1 of small diameter equipped with an outer race 2 and an inner race 3, and a plurality of rolling elements 4 disposed between the outer race 2 and the inner race 3, at least rolling element 4 is composed of a steel of Cr concentration being 8 wt % or higher, and the surface thereof is formed with a layer of N concentration being a range of 3≦N %≦0.26×Cr %+4.42.

Abstract: A method for surface processing of sintered oilless bearing and an apparatus thereof are disclosed by which method the efficiency of covering the pores and the surface roughness of protuberance that is nonporous surface may be improved by means of surface processing of inner diameter surface at time of sizing process using a correcting rod where many correction grooves have been formed on its top part.