公开(公告)号：US20240186841A1

公开(公告)日：2024-06-06

申请号：US18287723

申请日：2022-04-05

Applicant: Hitachi, Ltd.

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

IPC: H02K1/02 ,  H01F1/16 ,  H01F27/245

CPC classification number: H02K1/02 ,  H01F1/16 ,  H01F27/245

Abstract: A magnetic material includes body-centered tetragonal (bct) crystal including iron and nitrogen, in which a molar ratio of iron to nitrogen in the crystal exceeds 8. An iron core includes soft magnetic steel sheets stacked together, in which a part or the entirety of the soft magnetic steel sheets is formed of the magnetic material which includes body-centered tetragonal (bct) crystal including iron and nitrogen and has a molar ratio of iron to nitrogen in the crystal exceeds 8. A rotating electric machine includes an iron core including soft magnetic steel sheets stacked together, in which a part or the entirety of the soft magnetic steel sheets is formed of the magnetic material which includes body-centered tetragonal (bct) crystal including iron and nitrogen and has a molar ratio of iron to nitrogen in the crystal exceeds 8.

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：US20240233993A9

公开(公告)日：2024-07-11

申请号：US18278477

申请日：2021-09-28

Applicant: Hitachi, Ltd.

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

IPC: H01F1/16 ,  C21D9/46 ,  C22C38/00 ,  C22C38/10 ,  C22C38/12

CPC classification number: H01F1/16 ,  C21D9/46 ,  C22C38/001 ,  C22C38/10 ,  C22C38/12 ,  C21D2211/005 ,  C22C2202/02

Abstract: A soft magnetic iron alloy sheet has a saturation magnetic flux density comparable to that of Permendur, with the same iron loss as electromagnetic pure iron, and a lower cost than Permendur. The soft magnetic iron alloy sheet includes, as a chemical composition, 30 at % or less of Co, 0.1 at % or more and 11 at % or less of N, and 1.2 at % or less of vanadium, with the remainder being Fe and impurities. In a thickness direction of the soft magnetic iron alloy sheet, a surface layer region has an average nitrogen concentration of 1 at % or more and 15 at % or less and an internal region has a lower average nitrogen concentration than the surface layer region. In the surface layer region, a thickness is 1% or more and 30% or less from both main surfaces of the sheet and iron-nitride martensite having a tetragonal structure is formed.

公开(公告)号：US20240194383A1

公开(公告)日：2024-06-13

申请号：US18286240

申请日：2022-02-18

Applicant: Hitachi, Ltd.

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

IPC: H01F1/20 ,  C21D1/18 ,  C21D1/76 ,  C21D3/08 ,  C21D6/00 ,  C21D6/04 ,  C21D9/46 ,  C22C38/00 ,  C22C38/10

CPC classification number: H01F1/20 ,  C21D1/18 ,  C21D1/76 ,  C21D3/08 ,  C21D6/007 ,  C21D6/04 ,  C21D9/46 ,  C22C38/001 ,  C22C38/10 ,  C21D2211/008 ,  C22C2202/02

Abstract: A soft magnetic iron alloy plate having saturation magnetic flux density higher than that of an electromagnetic pure iron plate without an excessive increase in an iron loss, a method for manufacturing the soft magnetic iron alloy plate, and an iron core and a rotating electric machine using the soft magnetic iron alloy plate are provided. A soft magnetic iron alloy plate according to the present invention includes chemical composition containing 2 to 10 at. % of N, 0 to 30 at. % of Co, 0 to 1.2 at. % of V, and a remaining portion including Fe and impurities, and in a thickness direction of the soft magnetic iron alloy plate, an outer nitrogen concentration transition region where N concentration on a main surface is 1 to 4 at. % and N concentration increases toward the inner side from the main surface, a high nitrogen concentration region where maximum N concentration is higher than N concentration of the main surface and less than 11 at. %, and a variation range of N concentration is within 1 at. %, and an inner nitrogen concentration transition region where N concentration decreases toward the inner side from the high nitrogen concentration region and minimum N concentration is lower than N concentration in the high nitrogen concentration region and is 1 at. % or more.

公开(公告)号：US20240136096A1

公开(公告)日：2024-04-25

申请号：US18278477

申请日：2021-09-27

Applicant: Hitachi, Ltd.

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

IPC: H01F1/16 ,  C21D9/46 ,  C22C38/00 ,  C22C38/10 ,  C22C38/12

CPC classification number: H01F1/16 ,  C21D9/46 ,  C22C38/001 ,  C22C38/10 ,  C22C38/12 ,  C21D2211/005 ,  C22C2202/02

Abstract: A soft magnetic iron alloy sheet has a saturation magnetic flux density comparable to that of Permendur, with the same iron loss as electromagnetic pure iron, and a lower cost than Permendur. The soft magnetic iron alloy sheet includes, as a chemical composition, 30 at % or less of Co, 0.1 at % or more and 11 at % or less of N, and 1.2 at % or less of vanadium, with the remainder being Fe and impurities. In a thickness direction of the soft magnetic iron alloy sheet, a surface layer region has an average nitrogen concentration of 1 at % or more and 15 at % or less and an internal region has a lower average nitrogen concentration than the surface layer region. In the surface layer region, a thickness is 1% or more and 30% or less from both main surfaces of the sheet and iron-nitride martensite having a tetragonal structure is formed.