C21D 1/06
Surface hardening
C21D1/06 (Surface hardening) appears on 994 US grants and 1,125 published applications in this corpus.
Search patents in C21D- Granted patents
- 994
- Published applications
- 1,125
- Assignees
- 611
- Inventors
- 2,691
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 5 | 0 |
| 1977 | 6 | 0 |
| 1978 | 5 | 0 |
| 1979 | 6 | 0 |
| 1980 | 3 | 0 |
| 1981 | 7 | 0 |
| 1982 | 5 | 0 |
| 1983 | 5 | 0 |
| 1984 | 8 | 0 |
| 1985 | 11 | 0 |
| 1986 | 5 | 0 |
| 1987 | 14 | 0 |
| 1988 | 11 | 0 |
| 1989 | 12 | 0 |
| 1990 | 7 | 0 |
| 1991 | 5 | 0 |
| 1992 | 10 | 0 |
| 1993 | 14 | 0 |
| 1994 | 12 | 0 |
| 1995 | 10 | 0 |
| 1996 | 11 | 0 |
| 1997 | 9 | 0 |
| 1998 | 13 | 0 |
| 1999 | 22 | 0 |
| 2000 | 19 | 0 |
| 2001 | 19 | 2 |
| 2002 | 20 | 17 |
| 2003 | 14 | 12 |
| 2004 | 11 | 26 |
| 2005 | 14 | 21 |
| 2006 | 12 | 31 |
| 2007 | 10 | 27 |
| 2008 | 11 | 27 |
| 2009 | 11 | 40 |
| 2010 | 22 | 48 |
| 2011 | 14 | 39 |
| 2012 | 23 | 62 |
| 2013 | 27 | 44 |
| 2014 | 35 | 57 |
| 2015 | 30 | 64 |
| 2016 | 41 | 98 |
| 2017 | 51 | 73 |
| 2018 | 55 | 61 |
| 2019 | 66 | 84 |
| 2020 | 61 | 49 |
| 2021 | 50 | 43 |
| 2022 | 45 | 54 |
| 2023 | 34 | 55 |
| 2024 | 35 | 39 |
| 2025 | 25 | 32 |
| 2026 | 23 | 20 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Housing of an induction hardening tool6 Oct 2026US 12,752,288 B2Aktiebolaget Skf
- Surface-hardened, rotationally symmetrical workpiece, hardening method and hardening apparatus1 Sep 2026US 12,723,286 B2Walzengiesserei Coswig GmbH
- Method of heat treating a steel component18 Aug 2026US 12,709,781 B2Aktiebolaget Skf
- Method to produce high corrosion and wear resistant cast iron components by using laser cladding11 Aug 2026US 12,703,047 B2Oerlikon Surface Solutions AG, PfäFfikon
- Volume heat treatment method and related system4 Aug 2026US 12,698,541 B2Laser Engineering Applications
- Laser hardening installation for laser hardening a bearing component3 Sep 2026US 2026/0257300 A1
- Forged part of steel and a method of manufacturing thereof3 Sep 2026US 2026/0258537 A1
- Magnetically enhanced induction heat treating application27 Aug 2026US 2026/0250796 A1Ajax Tocco Magnethermic Corporation
- Steel for Cold Forging and Nitriding Excellent in Cold Forgeability and Nitriding Properties, and Cold-Forged and Nitrided Part Using Same13 Aug 2026US 2026/0234773 A1Sanyo Special Steel Co., Ltd.
- Mechanical component and method for manufacturing mechanical component13 Aug 2026US 2026/0235197 A1Komatsu Ltd.
Most cited
By later US patents
- Surface hardening of cams of motor-vehicle camshafts1,402US 4,312,685 AAudi NSU Auto Union Aktiengesellschaft · 1982
- Magnetically coded device145US 5,631,093 AGeneral Motors Corporation · 1997
- Laser beam shaping device and process including a rotating mirror105US 5,925,271 AFraunhofer-Gesellschaft zur Förderung der angewandten Forschung e. V. · 1999
- Skin melting101US 4,122,240 AUnited Technologies Corporation · 1978
- Surface modification99US 4,015,100 AAvco Everett Research Laboratory, Inc. · 1977