- All sections
- C - Chemistry; metallurgy
- C21D - Modifying the physical structure of ferrous metals; general devices for heat treatment of ferrous or non-ferrous metals or alloys; making metal malleable, e.g. by decarburisation or tempering
- C21D 1/18 - Hardening; Quenching with or without subsequent tempering
Patent holdings for IPC class C21D 1/18
Total number of patents in this class: 1727
10-year publication summary
|
170
|
163
|
151
|
161
|
196
|
153
|
137
|
144
|
181
|
177
|
| 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| Nippon Steel Corporation | 5819 |
198 |
| JFE Steel Corporation | 6289 |
148 |
| ArcelorMittal | 1983 |
115 |
| Nippon Steel & Sumitomo Metal Corporation | 1988 |
63 |
| POSCO Co., Ltd. | 1237 |
51 |
| Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | 2892 |
40 |
| NTN Corporation | 4987 |
36 |
| ThyssenKrupp Steel Europe AG | 935 |
36 |
| Voestalpine Stahl GmbH | 325 |
33 |
| Baoshan Iron & Steel Co., Ltd. | 858 |
31 |
| Nanjing Iron&Steel Co.,Ltd. | 143 |
18 |
| Hitachi Metals, Ltd. | 2124 |
16 |
| Caterpillar Inc. | 8978 |
16 |
| POSCO | 2211 |
15 |
| ThyssenKrupp AG | 3143 |
15 |
| Jiangyin Xingcheng Special Steel Works Co., Ltd. | 59 |
13 |
| Voestalpine Metal Forming GmbH | 69 |
12 |
| Aktiebolaget SKF | 2759 |
11 |
| GM Global Technology Operations LLC | 13686 |
10 |
| Tata Steel Ijmuiden B.V. | 292 |
10 |
| Other owners | 840 |