- All sections
- C - Chemistrymetallurgy
- C21D - Modifying the physical structure of ferrous metalsgeneral devices for heat treatment of ferrous or non-ferrous metals or alloysmaking metal malleable, e.g. by decarburisation or tempering
- C21D 1/25 - Hardening, combined with annealing between 300 °C and 600 °C, i.e. heat refining ("Vergüten")
Patent holdings for IPC class C21D 1/25
Total number of patents in this class: 292
10-year publication summary
|
31
|
22
|
33
|
21
|
14
|
24
|
20
|
23
|
7
|
12
|
| 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| JFE Steel Corporation | 7508 |
34 |
| ArcelorMittal | 2663 |
28 |
| Nippon Steel Corporation | 6843 |
19 |
| United States Steel Corporation | 172 |
9 |
| Hitachi Metals, Ltd. | 1900 |
6 |
| Baoshan Iron & Steel Co., Ltd. | 1101 |
6 |
| ThyssenKrupp Steel Europe AG | 989 |
6 |
| Voestalpine Stahl GmbH | 389 |
6 |
| Salzgitter Flachstahl GmbH | 163 |
5 |
| Aubert & Duval | 114 |
4 |
| Daido Steel Co., Ltd. | 284 |
4 |
| Tata Steel Nederland Technology BV | 161 |
4 |
| Nanjing Iron&Steel Co.,Ltd. | 186 |
4 |
| Caterpillar Inc. | 10272 |
3 |
| L.E. Jones Company, LLC | 21 |
3 |
| POSCO Co., Ltd. | 2006 |
3 |
| Rautaruukki Oyj | 136 |
3 |
| Uddeholms Aktiebolag | 205 |
3 |
| Robert Bosch GmbH | 44128 |
2 |
| Aisin AW Co., Ltd. | 2256 |
2 |
| Other owners | 138 |