Patent US4632910A successfully refreshed from Google Patents.
US4632910A
Expired / Lapsed
US
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Sintered material of silicon nitride for cutting tools and process therefor
Assignee: Korea Advanced Institute of Science and Technology
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Filing: 1985-05-29
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Granted: 1986-12-30
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Expires: 2005-05-29
Abstract
Abstract A sintered material based on silicon nitride for use in preparing cutting tools is provided. This material is prepared by sintering a mixture of silicon nitride containing 2-10 percent by weight of yttrium oxide, 1-5 percent by weight of aluminium oxide and 10-40 percent by weight of titanium carbide coated with titanium nitride under hot pressing or sintering followed by hot isostatic pressing at an elevated temperature ranging from 1600° C. to 1800° C. The coated titanium carbide in the form of powder can be formed by depositing a film of titanium nitride on the surface of titanium carbide in the presence of gaseous titanium tetrachloride, hydrogen and nitrogen under the partial pressure of 0.1 to 0.5 atmosphere at 1000° C. to 1500° C. The material can endow the cutting tools with higher toughness and strength and longer life.
Inventors
- 👤 June-Gunn Lee
- 👤 Young-Wook Kim
- 👤 Tae-Hee Park
- 👤 Long Choi
- 👤 Sang-Ho Lee
- 👤 Kam-Yong Jang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:22
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/593; B; B23; B23B; B23B27/00; B23B27/14; B23B27/148; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2993; Y10T82/00; Y10T82/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
63 words
A sintered material based on silicon nitride consisting essentially of 2 to 10 percent by weight of yttrium oxide, 1 to 5 percent by weight of aluminium oxide. 10 to 40 percent by weight of titanium carbide coated with titanium nitride and the balance of silicon nitride which has been subjected to hot pressing at elevated temperatures of 1600° C. to 1800° C.
Claim 2
Dependent Claim
63 words
A sintered material based on silicon nitride consisting essentially of 2 to 10 percent by weight of yttrium oxide, 1 to 5 percent by weight of aluminium oxide. 10 to 40 percent by weight of titanium carbide coated with titanium nitride and the balance of silicon nitride which has been subjected to hot pressing at elevated temperatures of 1600° C. to 1800° C.
Claim 3
Dependent Claim
26 words
The sintered material of claim 1, wherein said titanium carbide coated with titanium nitride is formed by depositing titanium nitride on the surface of titanium carbide.
Claim 4
Dependent Claim
64 words
A process for preparing a sintered material based on silicon nitride comprising sintering and hot isostatic pressing a mixture of 2 to 10 percent by weight of yttrium oxide, 1 to 5 percent by weight of aluminium oxide and 10 to 40 percent by weight of titanium carbide coated with titanium nitride in powder form at elevated temperatures of 1600° C. to 1800° C.
Claim 5
Dependent Claim
64 words
A process for preparing a sintered material based on silicon nitride comprising sintering and hot isostatic pressing a mixture of 2 to 10 percent by weight of yttrium oxide, 1 to 5 percent by weight of aluminium oxide and 10 to 40 percent by weight of titanium carbide coated with titanium nitride in powder form at elevated temperatures of 1600° C. to 1800° C.
Claim 6
Dependent Claim
39 words
The process of claim 3, wherein said titanium carbide coated with titanium nitride is formed by depositing a film of titanium nitride on the surface of titanium carbide under the action of gaseous titanium tetrachloride, hydrogen, argon and nitrogen.
Claim 7
Dependent Claim
60 words
The process of claim 4, wherein the partial pressure of each of titanium tetrachloride and hydrogen during said deposition is in the range of 0.1 and 0.5 atmosphere, the partial pressure of each of argon and nitrogen during said deposition is in the range of 0.3 to 0.7 atmosphere, and the reaction temperature ranges from 1000° C. to 1200° C.
Claim 8
Dependent Claim
65 words
The process of claim 3, wherein said titanium carbide coated with titanium nitride is formed by nitriding titanium carbide on its surface and wherein the partial pressure of hydrogen during said deposition is in the range of 0.001 to 0.01 atmospheres, the partial pressure of nitrogen in the range of 0.99 to 0.999 atmospheres and the reaction temperature ranges from 1000° C. to 1500° C.
References Cited (Backward Citations)
GB1601224A
Cited
JPS5632377A
Cited
US4280973A
Cited
US4497228A
Cited
GB2095702A
Cited
JPS57205374A
Cited
JPS57205376A
Cited
JPS5895662A
Cited
JPS58199782A
Cited
US4425141A
Cited
US4462817A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-29 | 1990-06-30 | 1990-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-29 | 1994-06-30 | 1994-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-29 | 1998-06-30 | 1998-12-30 | $7700.00 | Window Closed / Lapsed |