公开(公告)号：US12163555B2

公开(公告)日：2024-12-10

申请号：US16954997

申请日：2018-12-05

Applicant: NTN CORPORATION

Inventor： Masahiro Yamada ,  Chikara Ohki

IPC: F16C33/62 ,  C21D1/06 ,  C21D9/36 ,  C21D9/40 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/44 ,  C23C8/32 ,  C23C8/80

Abstract: 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 μm. 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 μm.

公开(公告)号：US20240342785A1

公开(公告)日：2024-10-17

申请号：US18752897

申请日：2024-06-25

Applicant: NIPPON STEEL CORPORATION

Inventor： Atsushi SUGAMA ,  Takatsugu KITORA

IPC: B21D31/00 ,  B21D24/00 ,  B21D53/10 ,  C21D9/40

CPC classification number: B21D31/005 ,  B21D24/00 ,  B21D24/005 ,  B21D53/10 ,  C21D9/40

Abstract: Provided is a method for manufacturing a tubular rotary component from a donut-shaped metal disc, wherein the generation of wrinkles or cracks due to a drawing process can be suppressed. This method for manufacturing a tubular rotary component 100B includes: an intermediate molding step in which the entirety of both surfaces of a donut-shaped metal disc 100 having a prescribed inner diameter D1 and outer diameter D2 are pressed by the respective tapered surfaces of a punch 10A and a die 20A provided with a prescribed taper to carry out bore-expansion drawing, thereby obtaining a frustoconical intermediate molded article 100A; and a final molding step in which the intermediate molded article 100A is pressed by a punch 10B and a die 20B having a desired shape to carry out bore-expansion drawing again, thereby obtaining a tubular rotary component 100B.

公开(公告)号：US20240318690A1

公开(公告)日：2024-09-26

申请号：US18579559

申请日：2021-07-23

Applicant: AKTIEBOLAGET SKF

Inventor： Mohamed SHERIF

IPC: F16C33/62 ,  C21D1/20 ,  C21D1/26 ,  C21D6/00 ,  C21D9/40 ,  C22C38/00 ,  C22C38/44 ,  C22C38/52 ,  C23C8/26 ,  F16C33/64

CPC classification number: F16C33/62 ,  C21D1/20 ,  C21D1/26 ,  C21D6/004 ,  C21D9/40 ,  C22C38/001 ,  C22C38/44 ,  C22C38/52 ,  C23C8/26 ,  F16C33/64 ,  F16C2204/72 ,  F16C2223/14

Abstract: A method of manufacturing a component of a rolling-element bearing includes: providing a steel body having a carbon content of less than 0.3 weight-%, a chromium content of greater than 8.0 weight-%, and a nitrogen content of less than 0.1 weight-%; high-temperature solution nitriding the steel body; after the high-temperature solution nitriding, performing an intermediate tempering process to reduce a size of austenite grains in the steel body; and after the intermediate tempering process, performing a reaustenitizing annealing. Also the component made by the method.

公开(公告)号：US20240117841A1

公开(公告)日：2024-04-11

申请号：US18527965

申请日：2023-12-04

Applicant: thyssenkrupp rothe erde Germany GmbH ,  thyssenkrupp AG

Inventor： Joerg ROLLMANN ,  Thomas HANDRECK ,  Bernd LUENEBURG ,  Matthias TOEFKE ,  Christian LIEWEN

IPC: F16C33/64 ,  B21H1/12 ,  C21D9/40 ,  F16C19/38

CPC classification number: F16C33/64 ,  B21H1/12 ,  C21D9/40 ,  F16C19/386 ,  F16C2220/44 ,  F16C2223/10 ,  F16C2240/18 ,  F16C2360/31

Abstract: A rotor bearing having a rolling bearing raceway in an unhardened core region of a rolling bearing ring element that further includes an outer layer hardened to a surface hardening depth wherein the rolling bearing raceway is formed by a roll, wherein a diameter of the roll is 8 to 25 times the surface hardening depth.

公开(公告)号：US20240035515A1

公开(公告)日：2024-02-01

申请号：US18025379

申请日：2021-09-16

Applicant: NTN Corporation

Inventor： Naoki FUJIMURA ,  Masahiro YAMADA ,  Chikara OHKI

IPC: F16C33/62 ,  F16C19/06 ,  C21D9/40 ,  C21D1/18 ,  C21D1/74 ,  C23C8/32

CPC classification number: F16C33/62 ,  F16C19/06 ,  C21D9/40 ,  C21D1/18 ,  C21D1/74 ,  C23C8/32 ,  C21D2211/003 ,  C21D2211/008

Abstract: A bearing part (10) is composed of a steel, and has a quench-hardened layer (11) in a surface of the bearing part. The quench-hardened layer includes a plurality of martensite crystal grains. The plurality of martensite crystal grains are classified into a first group and a second group. A minimum value of crystal grain sizes of the martensite crystal grains belonging to the first group is larger than a maximum value of crystal grain sizes of the martensite crystal grains belonging to the second group. A value obtained by dividing a total area of the martensite crystal grains belonging to the first group by the total area of the plurality of martensite crystal grains is more than or equal to 0.3. A value obtained by dividing, by the total area of the plurality of martensite crystal grains, a total area of the martensite crystal grains belonging to the first group except for a martensite crystal grain that has a minimum crystal grain size and that belongs to the first group is less than 0.3. An average grain size of the martensite crystal grains belonging to the first group is less than or equal to 1.5 μm. The quench-hardened layer (11) further includes a plurality of cementite grains. A number density of cementite grains each having a grain size of more than or equal to 1 μm is more than or equal to 0.025/μm2.

公开(公告)号：US11746394B2

公开(公告)日：2023-09-05

申请号：US17493484

申请日：2021-10-04

Applicant: HYUNDAI MOTOR COMPANY ,  KIA CORPORATION ,  SEOHAN INDUSTRY CO., LTD. ,  KOREA FLANGE CO., LTD

Inventor： Jeong Lyul Park ,  Wonkew Ban ,  Hyun Ho Yim ,  Chang-Gu Lee ,  Min-Gyu Kim

IPC: C21D9/40 ,  C21D1/42 ,  F16D3/205 ,  C21D1/18 ,  C21D9/00

CPC classification number: C21D9/40 ,  C21D1/18 ,  C21D1/42 ,  C21D9/0062 ,  F16D3/2055

Abstract: A method for manufacturing a trunnion for a constant velocity joint, the trunnion having a plurality of journal units provided outside around a hub unit, the method including a first step of manufacturing the trunnion, a second step of thermally treating a rounded outer circumferential surface of the journal unit, and a third step of thermally treating a connection unit disposed between the journal unit and the hub unit and having a diameter smaller than that of the journal unit.

公开(公告)号：US20230016175A1

公开(公告)日：2023-01-19

申请号：US17378792

申请日：2021-07-19

Applicant: Gaona Aero Material Co., Ltd. ,  AECC COMMERCIAL AIRCRAFT ENGINE CO., LTD. ,  Zhejiang Hiro Aviation Technology Co., Ltd. ,  CENTRAL IRON & STEEL RESEARCH INSTITUTE

Inventor： Beijiang ZHANG ,  Wenyun ZHANG ,  Chenggang TIAN ,  Aihua HUANG ,  Guodong ZHANG ,  Haijun XUAN ,  Chuanyong CHEN ,  Shuo HUANG ,  Heyong QIN ,  Qiang TIAN ,  Ran DUAN

IPC: C21D8/02 ,  C21D9/40 ,  C21D11/00 ,  G01L5/00

Abstract: The present application relates to the field of superalloy, disclosing a method for internal stress regulation in superalloy disk forgings by pre-spinning. The method includes: Step S1, determining a target revolution for regulating internal stress in the disk forgings, and determining a target deformation magnitude of plastic deformation required for regulating the internal stress by the pre-spinning of the disk forgings; and Step S2, performing the pre-spinning of the disk forgings by the target revolution, monitoring a deformation magnitude of the disk forgings, and stopping the pre-spinning when a monitored deformation magnitude of the disk forgings reaches the target deformation magnitude.

公开(公告)号：US20220412407A1

公开(公告)日：2022-12-29

申请号：US17782126

申请日：2020-11-26

Applicant: thyssenkrupp rothe erde Germany GmbH ,  thyssenkrupp AG

Inventor： Joerg ROLLMANN ,  Thomas HANDRECK ,  Bernd LUENEBURG ,  Matthias TOEFKE ,  Christian LIEWEN

IPC: F16C33/64 ,  B21H1/12 ,  F16C19/38 ,  C21D9/40

Abstract: A method for increasing load capacity of a surface-hardened rolling bearing raceway of a rolling bearing ring element may involve providing a rolling bearing ring element with an unhardened core region and, at least in certain portions, an outer layer hardened to a surface hardening depth. A rolling bearing raceway may be formed in a region of the hardened outer layer. The method may further involve hard rolling the rolling bearing raceway with a roll. The diameter of the roll is 8 to 25 times the surface hardening depth. A surface pressure prevailing in a rolling contact between the roll and the rolling bearing raceway during the hard rolling is between 2000 MPa and 3300 MPa. The method further involves machining the rolling bearing raceway after the hard rolling.

公开(公告)号：US20220389559A1

公开(公告)日：2022-12-08

申请号：US17827910

申请日：2022-05-30

Applicant: Aktiebolaget SKF

Inventor： Karl Åke Staffan Larsson ,  Marica Ersson

IPC: C23C8/32 ,  B23P15/00 ,  C23C8/80 ,  C21D9/36 ,  C21D9/40 ,  C21D1/06

Abstract: The present invention provides a method of heat treating a steel component including the sequential steps of: (a) carbonitriding the steel component; (b) quenching the steel component; (c) optionally tempering the steel component; and (d) ferritically nitrocarburizing the steel component.

公开(公告)号：US11459630B2

公开(公告)日：2022-10-04

申请号：US16962153

申请日：2019-01-22

Applicant: NIPPON STEEL CORPORATION

Inventor： Tatsuya Koyama ,  Kei Miyanishi ,  Yutaka Neishi

IPC: C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C21D9/40 ,  C21D6/00 ,  C21D7/06 ,  C22C38/20 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/30 ,  C22C38/32 ,  C22C38/38 ,  C22C38/44

Abstract: A bearing steel part having a predetermined chemical composition, in which the number density of oxide particles having an equivalent circle diameter of 5 μm or more, and containing CaO, Al2O3 and SiO2, such that the content ratio of Al2O3 with respect to the total mass of CaO, Al2O3, and SiO2 is 50% by mass or more, is 3.0/cm2 or less in an arbitrary cross section of the part, and in which the Vickers hardness at a depth of 50 μm from a rolling surface is 750 or more, and in which the compressive residual stress at the rolling surface is 900 MPa or more. Also provided is a steel bar for a bearing steel part that is suitable for obtaining the foregoing bearing steel part.