公开(公告)号：US20230304528A1

公开(公告)日：2023-09-28

申请号：US18005877

申请日：2021-09-24

Applicant: NIPPON STEEL CORPORATION ,  TOYOTA JIDOSHA KABUSHIKI KAISHA

Inventor： Tatsuhiko ABE ,  Manabu KUBOTA ,  Satoru OKAWA ,  Motoichi MURAKAMI ,  Takashi KOYAMA ,  Yusuke MORITA ,  Takeshi FUKUI ,  Yusuke INUKAI ,  Yuichiro KAJIKI

IPC: F16C3/06 ,  C22C38/38 ,  C22C38/06 ,  C22C38/02 ,  C22C38/60

CPC classification number: F16C3/06 ,  C22C38/02 ,  C22C38/06 ,  C22C38/38 ,  C22C38/60

Abstract: A crankshaft with improved seizure resistance is provided. A crankshaft (10) is a crankshaft including journals (11) and pins (12), having a chemical composition of, in mass %: 0.35 to 0.40 % C; up to 0.70 % Si; 1.00 to 2.00 % Mn; up to 0.50 % Cr; up to 0.050 % Al; up to 0.020 % N; up to 0.020 % P; 0.005 to 0.200 % S; and balance Fe and impurities, each of the journals (11) and pins (12) having a surface microstructure containing tempered martensite in not less than 80 volume % and a surface hardness not higher than HV 450.

公开(公告)号：US20210172470A1

公开(公告)日：2021-06-10

申请号：US17268807

申请日：2019-08-22

Applicant: NIPPON STEEL CORPORATION

Inventor： Tatsuhiko ABE ,  Manabu KUBOTA

IPC: F16C3/08 ,  B24B21/02 ,  B24B5/42

Abstract: A crankshaft with improved seizure resistance is provided. A crankshaft includes a journal and a pin, each of the journal and pin having such a surface geometry that the arithmetical mean height of the primary profile, Pa, is 0.090 μm or smaller and the reduced peak height Rpk is 0.070 μm or smaller. As used herein, arithmetical mean height of a primary profile Pa is defined in JIS B 0601 (2001), and reduced peak height Rpk is defined in JIS B 0671 (2002).

公开(公告)号：US20240392401A1

公开(公告)日：2024-11-28

申请号：US18692990

申请日：2022-10-26

Applicant: NIPPON STEEL CORPORATION

Inventor： Natsumi KIKUCHI ,  Kison NISHIHARA ,  Tatsuhiko ABE

IPC: C21D6/00 ,  C21D1/18 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/18

Abstract: A steel material for a sliding part with improved slidability and workability is provided. A steel material for a sliding part includes a steel material with a C content of 0.30 to 0.60 mass %, having a microstructure including (a) at least one of tempered martensite and bainite and (b) an iron carbide, the volume fraction of the tempered martensite and bainite combined being not lower than 80% and the volume fraction of the iron carbide being not lower than 2.0%, the Vickers hardness being not lower than 300 and not higher than 600, the volume fraction of the iron carbide, X, and the Vickers hardness, Hv, satisfying the following relational expression, (1): X ≥ - 0 . 0 ⁢ 65 × Hv + 36. 5 , ( 1 ) where X is in % and Hv is in Hv.

公开(公告)号：US20240044358A1

公开(公告)日：2024-02-08

申请号：US18264496

申请日：2022-03-04

Applicant: NIPPON STEEL CORPORATION

Inventor： Tatsuhiko ABE ,  Yoko SUEYASU

IPC: F16C3/08 ,  C22C38/24 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D9/30 ,  C21D8/00 ,  C21D6/00

CPC classification number: F16C3/08 ,  C22C38/24 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/002 ,  C22C38/001 ,  C21D9/30 ,  C21D8/005 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  F16C2240/18 ,  F16C2202/04 ,  F16C2220/70 ,  F16C2202/02 ,  F16C2204/62 ,  F16C2204/64 ,  F16C2204/74 ,  F16C2360/22

Abstract: 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 μm, the maximum value of the compressive residual stress being not lower than 1000 MPa, the surface roughness Rz being lower than 3.00 μm.

公开(公告)号：US20230146538A1

公开(公告)日：2023-05-11

申请号：US17759451

申请日：2021-02-19

Applicant: NIPPON STEEL CORPORATION

Inventor： Tatsuhiko ABE ,  Satoru OKAWA ,  Masato YUYA

IPC: F16C3/08

CPC classification number: F16C3/08 ,  F16C2223/02 ,  F16C2202/04 ,  F16C2202/10 ,  F16C2223/14 ,  F16C2223/30 ,  F16C2206/04 ,  C22C38/18

Abstract: A crankshaft with improved seizure resistance is provided. A crankshaft having journals 11 and pins 12 includes a compound layer containing iron and nitrogen on its surface, wherein, in the compound layer, for both the journals 11 and pins 12, the porosity area ratio of the thinner one of a region from the surface to a depth of 3.0 μm and a region across the total thickness of the compound layer is not higher than 10.0%, and both the journals 11 and pins 12 have such a surface geometry that the arithmetical mean deviation of the primary profile, Pa, is not larger than 0.090 μm.