Technology page · data to 2026-10-15
Mn–Bi (manganese-bismuth) magnet patents
If your team works on this technology, the risk is building next to a competitor's claim you have not read yet, often published only in Chinese, Japanese or Korean.
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Low-temperature-phase MnBi is a rare-earth-free magnet whose coercivity rises with temperature, which makes it interesting for hot motor environments. Filings cover alloy composition, phase purification, powder processing and bonded or hybrid magnets.
In our base
- 46 patent families (70 publications) published from 2021-09-30 to 2026-10-15.
- 9 new families in the last twelve months, against 8 in the twelve months before.
New families by year of first publication
* 2021 counts publications from 09-27, when our base starts.
* 2026 counts publications up to 10-15 only; new publications reach our sources weeks late, Chinese ones three weeks or more.
| Year | Families |
|---|---|
| 2021 | 5 |
| 2022 | 10 |
| 2023 | 9 |
| 2024 | 7 |
| 2025 | 8 |
| 2026 (to 10-15) | 7 |
Offices
A family counts once in each office where a member has published.
| Office | Families |
|---|---|
| CN | 34 |
| US | 11 |
| KR | 8 |
| WO | 5 |
| EP | 2 |
| JP | 1 |
Applicants with two or more families
Harmonised names from the source record; subsidiaries are not merged.
| Applicant | Families |
|---|---|
| Univ Jiliang China | 7 |
| Univ Tongji | 5 |
| Pan Minxiang | 4 |
| Univ Chongqing Sci & Tech | 3 |
| ABB Schweiz AG | 2 |
| Hyundai Motor Co Ltd | 2 |
| IUCF HYU ERICA Campus | 2 |
| Korea Institute Materials Science | 2 |
| Korea Institute Materials Science [KR] | 2 |
| Korecen Co Ltd | 2 |
Most recent publications
The newest publication in each of the 8 most recently active families, as recorded. Families our analysts have reviewed carry a note.
MnBiSn permanent magnet alloy with low activation energy and preparation method thereof
CN-117778803-B · published 2026-09-04 · Univ Tongji · offices: CN
CN-117778803-B is a Chinese grant for an MnBiSn permanent magnet alloy, Mn55Bi(45-x)Snx with x up to 2. It is made by vacuum induction melting and a three-hour anneal at 300 °C. The earlier application names Tongji University. Tin on bismuth sites lowers the activation energy for forming the magnetic low-temperature phase, the step that makes MnBi hard to produce. The abstract claims a large gain in energy product but gives no figure. Tongji is one of several Chinese universities filing on MnBi in our data, with China Jiliang University and Chongqing University of Science and Technology.
Mnbi-based magnet
WO-2026168979-A1 · published 2026-08-13 · LG Innotek Co Ltd; Nara Inst Of Science And Technology National University Corporation · offices: KR, WO
LG Innotek and the Nara Institute of Science and Technology claim a manganese-bismuth (MnBi) magnet with 2–10 atomic per cent ruthenium. Ruthenium as a third element sets the claim apart. LG Innotek has one other MnBi family in our data, so this is a continuing programme.
Mn-Bi based powder, method of preparing the same, and Mn-Bi based magnet comprising the same
KR-20260085679-A · published 2026-06-09 · Hyundai Motor Co Ltd; Kia Corp; Korea Inst Of Materials Science · offices: KR
Preparation method of high-performance permanent magnet composite powder
CN-117696904-B · published 2026-05-26 · Univ Jiliang China · offices: CN
MnBi permanent magnet preparation and performance regulation method
CN-122067917-A · published 2026-05-19 · Univ Chongqing Sci & Tech · offices: CN
CN-122067917-A (Chongqing University of Science and Technology) claims a method that deforms MnBi alloy mechanically to introduce dense crystal defects and fresh phase interfaces, then heat-treats it to promote formation of the magnetic low-temperature phase (LTP), controlling recrystallisation, grain size and phase. A high LTP fraction is the main production barrier for MnBi magnets. It is one of three MnBi-related filings from this university in our data.
Traction motor with Bonded Magnets
US-20260106496-A1 · published 2026-04-16 · ABB Schweiz AG · offices: CN, US
High-density anisotropic manganese bismuth sintered permanent magnet for motor and preparation method thereof
CN-121583675-A · published 2026-02-27 · Univ Chongqing Sci & Tech · offices: CN
CN-121583675-A (Chongqing University of Science and Technology) claims a high-density anisotropic sintered MnBi magnet for motors, combining rapid solidification, field orientation, isostatic pressing, two-stage heat treatment and a two-stage low-temperature sintering step that densifies the magnet below the temperature at which the LTP phase decomposes. Dense, oriented bulk MnBi is what motor use requires and has been hard to reach. The abstract names high-temperature motors as the target.
Rare-earth-free permanent magnet motor
US-20260031664-A1 · published 2026-01-29 · Univ Pittsburgh Commonwealth Sys Higher Education · offices: US
US-20260031664-A1 (University of Pittsburgh) claims stator-tooth configurations for rare-earth-free permanent magnet synchronous motors that reduce the risk of irreversible demagnetisation, with MnBi surface-magnet motors as the main case. MnBi loses coercivity at low temperature, which is what limits its torque and power density in motors; the filing addresses that through machine geometry rather than the material. It is a rare example of motor-design guidance written specifically for a rare-earth-free magnet.
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Publications come from the EPO Open Patent Services and Google Patents Public Data, matched against a published CPC and keyword scope and grouped by DOCDB patent family. New publications reach our sources several weeks after they are published (Chinese ones three weeks or more), so the latest weeks are incomplete.