公开(公告)号：US20230290551A1

公开(公告)日：2023-09-14

申请号：US18019518

申请日：2021-05-11

Applicant: Hitachi, Ltd.

Inventor： Matahiro KOMURO ,  Yusuke ASARI ,  Kazuya SHINAGAWA ,  Shinya TAMURA ,  Tomohiro TABATA ,  Shohei TERADA

IPC: H01F1/16 ,  H02K1/02 ,  C21D3/08 ,  C21D1/76 ,  C21D1/18 ,  C21D9/46 ,  C22C38/00 ,  C22C38/10 ,  C22C38/12 ,  C21D6/00

CPC classification number: H01F1/16 ,  H02K1/02 ,  C21D3/08 ,  C21D1/76 ,  C21D1/18 ,  C21D9/46 ,  C22C38/001 ,  C22C38/10 ,  C22C38/12 ,  C21D6/007 ,  C21D2211/001 ,  C22C2202/02

Abstract: The present invention provides a soft magnetic iron sheet exhibiting a high saturation magnetic flux density and a low iron loss as compared with an electromagnetic pure iron sheet, a method for producing the soft magnetic iron sheet, and, an iron core and a dynamo-electric machine, each using the soft magnetic iron sheet. The soft magnetic iron sheet according to the present invention includes: iron as a main component; and nitrogen, in which the soft magnetic iron sheet includes, along a thickness direction of the soft magnetic iron sheet: a high nitrogen concentration layer having a nitrogen concentration of 2 at. % to 11 at. %; a low nitrogen concentration layer having a nitrogen concentration of half or less of the nitrogen concentration of the high nitrogen concentration layer; and a nitrogen concentration transition layer connecting the nitrogen concentration of the high nitrogen concentration layer and the nitrogen concentration of the low nitrogen concentration layer, and wherein a surface layer region including at least both main surfaces of the soft magnetic iron sheet is the low nitrogen concentration layer.

公开(公告)号：US20230287546A1

公开(公告)日：2023-09-14

申请号：US18019897

申请日：2021-06-01

Applicant: Hitachi, Ltd.

Inventor： Kazuya SHINAGAWA ,  Matahiro KOMURO ,  Yusuke ASARI ,  Shohei TERADA

IPC: C22C38/10 ,  H01F1/20 ,  H02K1/02 ,  B22F1/142 ,  B22F1/054

CPC classification number: C22C38/105 ,  H01F1/20 ,  H02K1/02 ,  B22F1/142 ,  B22F1/054 ,  B22F2301/35 ,  B22F2304/054 ,  B22F2302/20 ,  C22C2202/02

Abstract: Provided are a soft magnetic material capable of achieving a high saturation density by reducing Co among soft magnetic materials made of a FeCo-based alloy, a method for producing a soft magnetic material, and an electric motor.
The soft magnetic material of the present invention is a soft magnetic material containing Fe and Co in a total amount of 90 mass % or more, in which: contained components are 50 mass % or more of Fe, 40 mass % or less of Co, 0.1 mass % or less of C, 2.0 mass % or less of Ni, 0.2 mass % or less of Mn, Si, Cr, Ti, Nb, and V, and inevitable impurities; and



the soft magnetic material contains a precipitate of a compound of iron and nitrogen. The precipitate is created by tension annealing a raw material of the soft magnetic material.

公开(公告)号：US20220380881A1

公开(公告)日：2022-12-01

申请号：US17773750

申请日：2020-09-04

Applicant: Hitachi, Ltd.

Inventor： Hisamitsu HATOU ,  Kazuya SHINAGAWA ,  Keigo NAKAMURA ,  Hiroshi KANEMOTO

IPC: C23C8/26 ,  C21D1/06

Abstract: The present invention provides a nitriding treatment method for forming a compound layer of ε phase (Fe2-3N) and γ′ phase (Fe4N) iron nitride excellent in wear durability in a steel material, from which a sliding member is formed, by short treatment, with a high thermal efficiency, with a reduced amount of used nitriding gas, and with a low environmental load. The nitriding treatment method of the present invention includes heating a sliding member made of a steel material at a temperature of 600° C. to 700° C. for a time of 1 to 25 minutes under an atmosphere of nitriding gas through high frequency induction heating or resistive heating, to form a compound layer of ε phase (Fe2-3N) and γ′ phase (Fe4N) iron nitride, the compound layer having a nitrogen content of higher than 4.5%, in a surface layer portion of the sliding member.