C23C8/32

Method for manufacturing high-carbon bearing steel and high-carbon bearing steel manufactured therefrom

Disclosed is a method for manufacturing high-carbon bearing steel, which include: heating a billet at a temperature of about 950 to 1,050° C. for about 70 to 120 minutes, rolling the billet to manufacture a wire rod, winding the wire rod to manufacture a wire rod coil, cooling the wire rod coil, and subsequently heat treating the wire rod coil for spheroidizing and carbonitriding, respectively. The bearing steel may include an amount of about 0.9 to 1.3 wt % of carbon (C), an amount of about 1.1 to 1.6 wt % of silicon (Si), an amount of about 1.0 to 1.5 wt % of manganese (Mn), an amount of about 1.5 to 1.9 wt % of chromium (Cr), an amount of about 0.2 to 0.6 wt % of nickel (Ni), an amount of about 0.1 to 0.3 wt % of molybdenum (Mo), and the balance iron (Fe) based on the total weight thereof.

Method for manufacturing high-carbon bearing steel and high-carbon bearing steel manufactured therefrom

Disclosed is a method for manufacturing high-carbon bearing steel, which include: heating a billet at a temperature of about 950 to 1,050° C. for about 70 to 120 minutes, rolling the billet to manufacture a wire rod, winding the wire rod to manufacture a wire rod coil, cooling the wire rod coil, and subsequently heat treating the wire rod coil for spheroidizing and carbonitriding, respectively. The bearing steel may include an amount of about 0.9 to 1.3 wt % of carbon (C), an amount of about 1.1 to 1.6 wt % of silicon (Si), an amount of about 1.0 to 1.5 wt % of manganese (Mn), an amount of about 1.5 to 1.9 wt % of chromium (Cr), an amount of about 0.2 to 0.6 wt % of nickel (Ni), an amount of about 0.1 to 0.3 wt % of molybdenum (Mo), and the balance iron (Fe) based on the total weight thereof.

BRAKING BAND OF A DISK FOR DISK BRAKE

A braking band having an annular band body arranged around a rotation axis and made of one of gray cast iron, steel, aluminum or alloys thereof, has at least one braking surface having an activated band body portion for increasing adhesive capacity of at least one protective surface coating placed on the surface of the activated band body portion and having at least one material with elevated resistance to abrasion. The activated band body portion is arranged on the surface of the annular band body to form an outermost layer of the braking band with the at least one protective surface coating and has a rough profile having at least one channel delimited by at least one pair of projections, extending along a path at least partially surrounding the rotation axis and having a channel bottom and a first channel side forming an acute angle with the channel bottom and an opposite second channel side forming an obtuse angle with the channel bottom.

BRAKING BAND OF A DISK FOR DISK BRAKE

A braking band having an annular band body arranged around a rotation axis and made of one of gray cast iron, steel, aluminum or alloys thereof, has at least one braking surface having an activated band body portion for increasing adhesive capacity of at least one protective surface coating placed on the surface of the activated band body portion and having at least one material with elevated resistance to abrasion. The activated band body portion is arranged on the surface of the annular band body to form an outermost layer of the braking band with the at least one protective surface coating and has a rough profile having at least one channel delimited by at least one pair of projections, extending along a path at least partially surrounding the rotation axis and having a channel bottom and a first channel side forming an acute angle with the channel bottom and an opposite second channel side forming an obtuse angle with the channel bottom.

STEEL COMPONENT

Provided is a steel component with excellent surface fatigue strength. The steel component has a nitride compound layer with a thickness of 5.0 μm to 30.0 μm and a hardened layer in an order from a component surface to a component inside, where a thickness of a porous layer on an outermost surface of the nitride compound layer is 3.0 μm or less and 40.0% or less of a thickness of the nitride compound layer, and the hardened layer has a hardness of HV600 or more at a position of 50 μm inward from the component surface, a hardness of HV400 or more at a position from the component surface to the component inside of 400 μm, and a hardness of HV250 or more at a position from the component surface to the component inside of 600 μm.

ROLLING BEARING
20220411891 · 2022-12-29 ·

A rolling bearing is a tapered roller bearing, a cylindrical roller bearing, or a deep groove ball bearing including an inner ring, an outer ring, and a rolling element, each of the inner ring, the outer ring, and the rolling element being composed of a steel, the rolling bearing having a quench-hardened layer in at least one of an inner ring raceway surface of the inner ring, an outer ring raceway surface of the outer ring, and a rolling contact surface of the rolling element. A ratio of a total area of a plurality of martensite crystal grains in the quench-hardened layer is more than or equal to 70%. The plurality of martensite crystal grains are classified into a first group and a second group. An average grain size of the martensite crystal grains belonging to the first group is less than or equal to 0.97 μm.

ROLLING BEARING
20220411891 · 2022-12-29 ·

A rolling bearing is a tapered roller bearing, a cylindrical roller bearing, or a deep groove ball bearing including an inner ring, an outer ring, and a rolling element, each of the inner ring, the outer ring, and the rolling element being composed of a steel, the rolling bearing having a quench-hardened layer in at least one of an inner ring raceway surface of the inner ring, an outer ring raceway surface of the outer ring, and a rolling contact surface of the rolling element. A ratio of a total area of a plurality of martensite crystal grains in the quench-hardened layer is more than or equal to 70%. The plurality of martensite crystal grains are classified into a first group and a second group. An average grain size of the martensite crystal grains belonging to the first group is less than or equal to 0.97 μm.

METHOD TO PRODUCE CAST IRON BRAKE DISCS WITH HIGH CORROSION AND WEAR RESISTANCE
20220403901 · 2022-12-22 ·

Method for producing a mechanically and preferably machined cast iron or grey cast iron surface, in particular on a brake disc, with increased wear and corrosion resistance, characterized in that said surface is subjected to a water jet treatment—usually according to the so-called fluid jet process, which is adjusted so that it completely or at least partially clears the cavities opened by the machining, which contain a graphite inclusion surrounded by the basic structure, so that in the latter case the level of the graphite inclusion lies below the outer surface of the basic structure surrounding the cavity, whereupon a diffusion layer is applied by nitrocarburizing and an oxide layer is applied on the diffusion layer.

METHOD TO PRODUCE CAST IRON BRAKE DISCS WITH HIGH CORROSION AND WEAR RESISTANCE
20220403901 · 2022-12-22 ·

Method for producing a mechanically and preferably machined cast iron or grey cast iron surface, in particular on a brake disc, with increased wear and corrosion resistance, characterized in that said surface is subjected to a water jet treatment—usually according to the so-called fluid jet process, which is adjusted so that it completely or at least partially clears the cavities opened by the machining, which contain a graphite inclusion surrounded by the basic structure, so that in the latter case the level of the graphite inclusion lies below the outer surface of the basic structure surrounding the cavity, whereupon a diffusion layer is applied by nitrocarburizing and an oxide layer is applied on the diffusion layer.

Sliding Component and Method for Manufacturing Same

Provided is a sliding component having a low coefficient of friction and capable of exerting stable sliding characteristics from the initial stage of sliding, and a manufacturing method capable of easily manufacturing the sliding component. A sliding component (1) includes an iron substrate (10), in which graphite particles (13) are dispersed in an iron base (11), and a tin coating (20) formed on the iron substrate (10), the tin coating (20) including tin as a main material. The graphite particles (13) of the sliding component (1) are exposed through the tin coating (20). The manufacturing method includes: a preparation step of preparing an iron substrate (10) including graphite particles (13) dispersed in an iron base (11); and a film forming step of forming a tin coating (20) on the surface of the iron substrate (10), the tin coating (20) including tin as a main material. The film forming step forms the tin coating (20) so that the graphite particles (13) are exposed through the tin coating (20).