Patent US5139720A successfully refreshed from Google Patents.
US5139720A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing sintered ceramic material
Assignee: KOMATSU SEISAKUSHO A Corp OF JAPAN KK
•
Filing: 1990-06-12
•
Granted: 1992-08-18
•
Expires: 2010-06-12
Abstract
Abstract In a method of manufacturing a sintered ceramic material using the heat generated in a thermit reaction as a heating source, a pre-heating is applied preceding to the sintering step or a mixture comprising: (A) at least one ceramic powder, (B) at least one non-metallic powder selected from the group consisting of carbon, boron and silicon, and (C) a metal powder and/or a non-metallic powder other than the above-mentioned (B) is used. Homogeneous and dense sintered ceramic material or sintered composite ceramic material can be obtained by this method, and the fine texture thereof, and the phase constitution, the phase distribution and the like of the composite ceramic phase can be controlled sufficiently.
Inventors
- 👤 Shuichi Takeda
- 👤 Hideki Shishiba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:31
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/64; C04B35/645; C04B35/6455; C04B35/65; C04B35/651
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
59 words
A method of manufacturing a sintered ceramic material which comprises a step of previously applying a pre-heating to a powder to be sintered at a predetermined temperature for a predetermined period of time and a step of applying heat-sintering to the powder to be sintered applied with said pre-heating by the heat generated in a thermit reaction under pressure.
Claim 2
Independent Claim
59 words
A method of manufacturing a sintered ceramic material which comprises a step of previously applying a pre-heating to a powder to be sintered at a predetermined temperature for a predetermined period of time and a step of applying heat-sintering to the powder to be sintered applied with said pre-heating by the heat generated in a thermit reaction under pressure.
Claim 3
Dependent Claim
30 words
A method as defined in claim 1, wherein the pre-heating is conducted by vacuum heating or an atmospheric heating in an inert atmosphere, a reducing atmosphere or an oxidative atmosphere.
Claim 4
Dependent Claim
19 words
A method as defined in claim 2, wherein the pre-heating is conducted at a temperature higher than 500° C.
Claim 5
Dependent Claim
18 words
A method as defined in claim 1, wherein a preliminary molding is applied previously preceding to the pre-heating.
Claim 6
Dependent Claim
23 words
A method as defined in claim 4, wherein the preliminary molding is conducted by a cold isostatic molding or hot isostatic molding method.
Claim 7
Dependent Claim
20 words
A method as defined in claim 1, wherein the heat-sintering is conducted under a pressure of higher than 200 atm.
Claim 8
Dependent Claim
65 words
A method as defined in claim 1, wherein the sintering step by the heat generated in the thermit reaction is further followed by post-heating at a predetermined temperature for a predetermined period of time for the improvement of the reliability and the performance of the sintered material without changing the fine texture of the resultant sintered ceramic material and the homogenity of the fine texture.
Claim 9
Dependent Claim
30 words
A method as defined in claim 7, wherein the post-heating is conducted by vacuum heating or an atmospheric heating is an inert atmosphere, a reducing atmosphere or an oxidative atmosphere.
Claim 10
Dependent Claim
23 words
A method as defined in claim 7, wherein the post-heating is conducted under pressure of 1 to 200 atm to the sintered material.
Claim 11
Dependent Claim
27 words
A method as defined in claim 8 or 9, wherein the post-heating is conducted by hot isostatic press, hot press or heat treatment under a normal temperature.
Claim 12
Dependent Claim
33 words
A method as defined in claim 1, wherein the powder to be sintered comprises one or more of ceramic powder or a mixture of a ceramic powder and a non-metallic and/or metal powder.
Claim 13
Independent Claim
62 words
A method of manufacturing a sintered composite ceramic material, wherein a mixture comprising: (A) at least one ceramic powder, (B) at least one of non-metallic powders selected from the group consisting of carbon, boron and silicon and (C) a metal powder and/or a non-metallic powder different from (B) described above is heat-sintered by the heat generated in a thermit reaction under pressure.
Claim 14
Independent Claim
62 words
A method of manufacturing a sintered composite ceramic material, wherein a mixture comprising: (A) at least one ceramic powder, (B) at least one of non-metallic powders selected from the group consisting of carbon, boron and silicon and (C) a metal powder and/or a non-metallic powder different from (B) described above is heat-sintered by the heat generated in a thermit reaction under pressure.
Claim 15
Dependent Claim
31 words
A method as defined in claim 12, wherein the thermit composition for heating the powder mixture to be sintered is a mixture comprising a copper oxide powder and an aluminum powder.
Claim 16
Dependent Claim
46 words
A method as defined in claim 12, wherein the thermit composition for heating the powder mixture to be sintered comprises a combination of a mixture of a copper oxide powder and an aluminum powder and a mixture of an iron oxide powder and an Si powder.
Claim 17
Dependent Claim
20 words
A method as defined in claim 12, wherein the heat-sintering is conducted under a pressure of higher than 200 atm.
Claim 18
Dependent Claim
57 words
A method as defined in claim 12, wherein the sintering step for the composite ceramic is followed by post-heating at a predetermined temperature for a predetermined period of time for reducing the porosity and improving the reliability and the performance without changing the fine texture, phase composition, structure or the like of the resultant sintered composite material.
Claim 19
Dependent Claim
30 words
A method as defined in claim 16, wherein the post-heating is conducted by vacuum heating or an atmospheric heating in an inert atmosphere, a reducing atmosphere or an oxidative atmosphere.
Claim 20
Dependent Claim
28 words
A method as defined in claim 16, wherein the post-heating is conducted by a hot isostatic press, hot press or a heat heat treatment under a normal pressure.
Claim 21
Dependent Claim
46 words
A method as defined in claim 16, wherein a hot isostatic press or hot press treatment is applied for 5 to 60 min at a temperature of 500° to 1700° C. and under a pressure within a range of 200 to 2000 atm as the post-treatment.
Claim 22
Dependent Claim
34 words
A method as defined in claim 12, wherein the powder mixture to be sintered is previously applied with pre-heating at a predetermined temperature for a predetermined period of time preceding to the sintering step.
Claim 23
Dependent Claim
29 words
A method as defined in claim 20, wherein the pre-heating is conducted by vacuum heating or atmospheric heating in an inert atmosphere, a reducing atmosphere or an oxidative atmosphere.
Claim 24
Dependent Claim
19 words
A method as defined in claim 21, wherein the pre-heating is conducted at a temperature higher than 500° C.
References Cited (Backward Citations)
US4062985A
Cited
US4150975A
Cited
JPS57166369A
Cited
JPS57166375A
Cited
JPS60226460A
Cited
EP0165707A2
Cited
JPS61186404A
Cited
US4689077A
Cited
EP0314492A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-18 | 1996-02-17 | 1996-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-18 | 2000-02-17 | 2000-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-18 | 2004-02-17 | 2004-08-18 | $7700.00 | Window Closed / Lapsed |