US4619798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing parts for use to the heat processing furnace
Assignee: Coorstek KK
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Filing: 1984-12-24
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Granted: 1986-10-28
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Expires: 2004-12-24
Abstract
Abstract A method of manufacturing extremely high purity parts for use to the heating furnace comprising adding a sintering assistant of 0.5-2.0 weight % and a binder, to SiC powder which has an average particle diameter of 2 μm or less, and molding it to a predetermined form; applying the purification treatment to this molded body by placing it in the 800°-1,300° C. atmosphere of a gas which is selected from a group consisting of halogen gas and hydrogen halide; degassing the purified molded body in vacuum under a temperature higher than that employed at the purification treatment; sintering the degassed molded body, and coating an SiC film on at least part of the sintered body according to the chemical vapor deposition.
Inventors
- 👤 Takashi Tanaka
- 👤 Kenro Hayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:03
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B41/45; C04B41/50; C04B41/5053; C04B41/5057; C04B41/5059; C04B41/80; C04B41/81; C04B41/85; C04B41/87; C30; C30B; C30B31/00; C30B31/06; C30B31/10; C30B35/00; C30B35/002
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
116 words
A method of manufacturing parts for a heating furnace comprising: (a) adding a sintering assistant of 0.5-2.0 wt. % and a binder, to SiC powder which has an average particle diameter of 2 μm or less, and molding it to a predetermined form: (b) purifying the molded body by placing it in an atmosphere consisting essentially of of halogen gas or hydrogen halide gas at a temperature in the range of 800°-1300° C.; (c) degassing the purified molded body in a vacuum under a temperature higher than that employed during said purification; (d) sintering the degassed molded body; and (e) coating a SiC film on at least part of the sintered body by chemical vapor deposition.
Claim 2
Independent Claim
116 words
A method of manufacturing parts for a heating furnace comprising: (a) adding a sintering assistant of 0.5-2.0 wt. % and a binder, to SiC powder which has an average particle diameter of 2 μm or less, and molding it to a predetermined form: (b) purifying the molded body by placing it in an atmosphere consisting essentially of of halogen gas or hydrogen halide gas at a temperature in the range of 800°-1300° C.; (c) degassing the purified molded body in a vacuum under a temperature higher than that employed during said purification; (d) sintering the degassed molded body; and (e) coating a SiC film on at least part of the sintered body by chemical vapor deposition.
Claim 3
Dependent Claim
18 words
The method according to claim 1, wherein said SiC powder has an average particle diameter of 0.5-1.5 μm.
Claim 4
Dependent Claim
24 words
The method according to claim 1, wherein said sintering assistant is at least one selected from the group consisting of boron and boron carbide.
Claim 5
Dependent Claim
16 words
The method according to claim 1, wherein the amount of said sintering assistant ranges from 0.5%-1.0%.
Claim 6
Dependent Claim
26 words
A method according to claim 1, wherein said binder is at least one selected from the group consisting of phenol resin, polyvinyl alcohol and methyl cellulose.
Claim 7
Dependent Claim
18 words
The method according to claim 1, wherein said molding is effected by rubber pressing, extrusion or slip casting.
Claim 8
Dependent Claim
17 words
The method according to claim 1, wherein the temperature employed during purification ranges from 900° C.-1000° C.
Claim 9
Dependent Claim
21 words
The method according to claim 1, wherein said halogen gas is selected from the group consisting of chlorine, bromine and fluorine.
Claim 10
Dependent Claim
25 words
The method according to claim 1, wherein said hydrogen halide gas is selected from the group consisting of hydrogen chloride, hydrogen bromide and hydrogen fluoride.
Claim 11
Dependent Claim
18 words
The method according to claim 1, wherein said degassing is carried out at a temperature of 1,350°-1,700° C.
Claim 12
Dependent Claim
18 words
The method according to claim 1, wherein said sintering is carried out at a temperature of 2,050°-2,100° C.
Claim 13
Dependent Claim
14 words
The method according to claim 1, wherein said SiC film is 100-300 μm thick.
Claim 14
Dependent Claim
15 words
The method according to claim 1, wherein said heating furnace parts are diffusion furnace parts.
Claim 15
Dependent Claim
20 words
The method according to claim 13, wherein said diffusion furnace parts are a process tube, a paddle or a boat.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1989-10-27 | 1990-04-28 | 1990-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-10-27 | 1994-04-28 | 1994-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-10-27 | 1998-04-28 | 1998-10-28 | $7700.00 | Window Closed / Lapsed |