US4511411A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming a hard surface layer on a metal component
Assignee: Vereinigte Drahtwerke AG
•
Filing: 1983-09-02
•
Granted: 1985-04-16
•
Expires: 2003-09-02
Abstract
Abstract A component of titanium or alloys thereof is placed in an autoclave. Nitrogen gas or ammonia is pumped into the autoclave. The chemically untreated component is exposed in the autoclave for three hours to a pressure of 900 bar and a temperature of 1000° C. The TiN layer thus formed in the surface- and subsurface-zone of the component has a Vickers hardness of 800 0 .05 g/sq.mm. with a thickness of 20 microns. With this economical method, an increase in surface hardness from Vickers hardness 0 .05 =450 with prior art methods to Vickers hardness 0 .05 =800 is achieved.
Inventors
- 👤 Paul Brunner
- 👤 Beat Hofer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:39
CPC Classifications
C; C23; C23C; C23C28/00; C23C28/04; C23C28/044; C23C28/048; C23C8/00; C23C8/06; C23C8/08; C23C8/24
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
90 words
A method of forming a nitride layer in the surface- and subsurface-zone of a component made of elements selected from the group consisting of Ti, Zr, Hf, Si, V, Nb, Ta, Cr, Mo, W and alloys thereof, comprising the steps of exposing the chemically untreated component in an autoclave with an atmosphere of nitrogen gas to an isostatic pressure of at least 100 bar and a temperature of at least 200° C. for at least one hour, and thereafter slowly reducing the pressure and the heat in the autoclave steadily.
Claim 2
Independent Claim
90 words
A method of forming a nitride layer in the surface- and subsurface-zone of a component made of elements selected from the group consisting of Ti, Zr, Hf, Si, V, Nb, Ta, Cr, Mo, W and alloys thereof, comprising the steps of exposing the chemically untreated component in an autoclave with an atmosphere of nitrogen gas to an isostatic pressure of at least 100 bar and a temperature of at least 200° C. for at least one hour, and thereafter slowly reducing the pressure and the heat in the autoclave steadily.
Claim 3
Dependent Claim
21 words
The method of claim 1, wherein a continuous, uniformly distributed nitride layer about 20 microns thick is formed on the component.
Claim 4
Dependent Claim
35 words
The method of claim 1, comprising the further step of applying at least one further hardening layer upon said nitride layer by a deposit selected from the group consisting of chemical and physical vapor-phase deposit.
References Cited (Backward Citations)
US1793309A
Cited
GB1573891A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-15 | 1988-10-15 | 1989-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-15 | 1992-10-15 | 1993-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-15 | 1996-10-15 | 1997-04-16 | $7700.00 | Window Closed / Lapsed |