Patent US5380408A successfully refreshed from Google Patents.
US5380408A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Etching process
Assignee: Sandvik Intellectual Property AB
•
Filing: 1992-12-22
•
Granted: 1995-01-10
•
Expires: 2012-12-22
Abstract
Abstract The present invention relates to an etching process for the purpose of removing binder phase from the surface of a hard metal consisting of hard material in a binder phase based on cobalt and/or nickel. By carrying out the etching process electrolytically in a mixture containing concentrated sulfuric acid and concentrated phosphoric acid at a volume ratio of 0.5-2 with a water content of <50% at a temperature of 25°-60° C. an even binder phase removal without deep penetration is achieved.
Inventors
- 👤 Rolf Svensson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 02:53
CPC Classifications
C; C25; C25F; C25F3/00; C25F3/02; Y; Y10; Y10S; Y10S427/00; Y10S427/103
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
78 words
A method for removing a layer of binder phase formed on the surface of a hard material insert containing hard constituents in a binder phase based on cobalt and/or nickel, comprising removing said layer of binder phase formed on the surface of said insert by etching said insert electrolytically in a mixture of concentrated sulfuric acid and concentrated phosphoric acid in a volume ratio of 0.5-2 with a water content of <50% at a temperature of 25°-60° C.
Claim 2
Independent Claim
78 words
A method for removing a layer of binder phase formed on the surface of a hard material insert containing hard constituents in a binder phase based on cobalt and/or nickel, comprising removing said layer of binder phase formed on the surface of said insert by etching said insert electrolytically in a mixture of concentrated sulfuric acid and concentrated phosphoric acid in a volume ratio of 0.5-2 with a water content of <50% at a temperature of 25°-60° C.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein the surface of the hard material inserts is initially subjected to a mechanical treatment before the electrolytic etching step.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein said hard constituents comprise WC.
Claim 5
Dependent Claim
11 words
The method of claim 3 wherein said binder phase is cobalt.
Claim 6
Dependent Claim
30 words
The method of claim 1 wherein said mixture of concentrated sulfuric acid and concentrated phosphoric acid is in a volume ratio 0.75 to 1.25 with a water content of <25%.
Claim 7
Dependent Claim
30 words
The method of claim 5 wherein said mixture of concentrated sulfuric acid and concentrated phosphoric acid is in a volume ratio 0.95 to 1.05 with a water content of <15%.
Claim 8
Dependent Claim
30 words
The method of claim 1 wherein said surface further contains a graphite layer overlying said binder phase layer, said graphite layer being essentially removed prior to said electrolytic etching step.
Claim 9
Dependent Claim
30 words
The method of claim 1 wherein after said etching, a thin, wear-resistant layer of a metal carbide, oxide, nitride or mixtures thereof or diamond is deposited on said etched surface.
Claim 10
Independent Claim
94 words
A method for removing a layer of binder phase formed on the surface of a hard material insert, comprising removing a binder enriched layer formed on the surface of a hard material insert containing hard constituents in a binder phase based on cobalt and/or nickel, without removal of binder phase in channels between the hard material grains in said insert, by etching said inserts electrolytically in a mixture of concentrated sulfuric acid and concentrated phosphoric acid in a volume ratio of 0.5-2 with a water content of <50% at a temperature of 25°-60° C.
Claim 11
Independent Claim
94 words
A method for removing a layer of binder phase formed on the surface of a hard material insert, comprising removing a binder enriched layer formed on the surface of a hard material insert containing hard constituents in a binder phase based on cobalt and/or nickel, without removal of binder phase in channels between the hard material grains in said insert, by etching said inserts electrolytically in a mixture of concentrated sulfuric acid and concentrated phosphoric acid in a volume ratio of 0.5-2 with a water content of <50% at a temperature of 25°-60° C.
Claim 12
Independent Claim
95 words
A method of treating a hard material insert having a surface layer containing cobalt and/or nickel and a base layer containing hard constituents in a binder phase based on cobalt and/or nickel, comprising removing said surface layer of cobalt and/or nickel from said base layer without formation of pores by removal of binder phase between said hard constituents in said base layer by etching said insert in a mixture of concentrated sulfuric acid and concentrated phosphoric acid in a volume ratio of 0.5-2 with a water content of <50% at a temperature of 25°-60° C.
Claim 13
Independent Claim
95 words
A method of treating a hard material insert having a surface layer containing cobalt and/or nickel and a base layer containing hard constituents in a binder phase based on cobalt and/or nickel, comprising removing said surface layer of cobalt and/or nickel from said base layer without formation of pores by removal of binder phase between said hard constituents in said base layer by etching said insert in a mixture of concentrated sulfuric acid and concentrated phosphoric acid in a volume ratio of 0.5-2 with a water content of <50% at a temperature of 25°-60° C.
References Cited (Backward Citations)
US2334698A
Cited
US2334699A
Cited
US2338321A
Cited
US2429676A
Cited
US2440715A
Cited
US2594124A
Cited
US2493579A
Cited
US2550544A
Cited
US2820750A
Cited
US4169026A
Cited
US4140597A
Cited
US4282289A
Cited
US4610931A
Cited
JPS6353269A
Cited
US4740280A
Cited
JPS6350279A
Cited
JPS6360280A
Cited
US4710279A
Cited
US4911989A
Cited
US5135801A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-01-09 | 1998-07-11 | 1999-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-09 | 2002-07-11 | 2003-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-09 | 2006-07-11 | 2007-01-10 | $7700.00 | Window Closed / Lapsed |