Patent US5989476A successfully refreshed from Google Patents.
US5989476A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of making a molded refractory article
Assignee: 3D Systems Inc
•
Filing: 1998-06-12
•
Granted: 1999-11-23
•
Expires: 2018-06-12
Abstract
Abstract A method for making a molded refractory article including the steps of providing a mold including a master pattern, the mold and master pattern defining a mold cavity; filling the mold cavity with a mixture comprising refractory particles and a heat fugitive binder; placing the assembly of the mold, master pattern and mixture in a furnace; curing the mixture; separating the mold and master pattern from the cured mixture; removing the binder to form a porous structure, sintering the porous structure to provide a porous refractory article and infiltrating the porous refractory article with a filler metal.
Inventors
- 👤 Michael S. Lockard
- 👤 Kris Schmidt
- 👤 Charles W. Hull
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:12
CPC Classifications
C; C22; C22C; C22C1/00; C22C1/10; C22C1/1005; C22C1/1015; B; B22; B22F; B22F3/00; B22F3/10; B22F3/1017; B22F3/1021; B22F3/12; B22F3/1208; B22F3/1258; B22F3/1283; B22F3/1291; B22F2998/00; B22F2998/10; B22F2999/00; B33; B33Y; B33Y80/00; Y; Y02; Y02P; Y02P10/00; Y02P10/25
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
180 words
A method for making a molded refractory article comprising the steps of: a) providing a mold including a master pattern, the mold and master pattern defining a molding pattern, at least the master pattern being formed using a stereolithographic or selective deposition modeling process; b) filling the molding pattern in proximity to the master pattern with a mixture comprising refractory particles and a heat fugitive binder; c) curing the mixture; d) heating the mold and cured mixture to a predetermined temperature for a predetermined time so as to cause the master pattern to melt, oxidize, or reduce, leaving a molded refractory particle/binder article with a mold pattern thereon substantially duplicating the master pattern; e) heating the molded refractory particle/binder article to a temperature sufficient to cause the binder to leave the molded refractory particle/binder article to form a porous refractory article, and f) heating the porous refractory article to a temperature greater than in step e) to cause the refractory particles to adhere to each other forming a sintered porous refractory article; the resultant product being a porous refractory article.
Claim 2
Independent Claim
180 words
A method for making a molded refractory article comprising the steps of: a) providing a mold including a master pattern, the mold and master pattern defining a molding pattern, at least the master pattern being formed using a stereolithographic or selective deposition modeling process; b) filling the molding pattern in proximity to the master pattern with a mixture comprising refractory particles and a heat fugitive binder; c) curing the mixture; d) heating the mold and cured mixture to a predetermined temperature for a predetermined time so as to cause the master pattern to melt, oxidize, or reduce, leaving a molded refractory particle/binder article with a mold pattern thereon substantially duplicating the master pattern; e) heating the molded refractory particle/binder article to a temperature sufficient to cause the binder to leave the molded refractory particle/binder article to form a porous refractory article, and f) heating the porous refractory article to a temperature greater than in step e) to cause the refractory particles to adhere to each other forming a sintered porous refractory article; the resultant product being a porous refractory article.
Claim 3
Dependent Claim
45 words
The method of claim 1, also including the step of infiltrating the sintered porous article with a metallic filler wherein the infiltrating step utilizes a relatively low melting point molten metal infiltrant to fill the pores, the resultant product being an article having a cavity.
Claim 4
Dependent Claim
13 words
The method of claim 1 wherein step a) and b) are performed simultaneously.
Claim 5
Dependent Claim
18 words
The method of claim 1 wherein the heat applied in step e) is greater than in step d).
Claim 6
Dependent Claim
29 words
The method of claim 1 wherein all of the steps are performed in a single oven programmed with temperatures and time periods sufficient to perform each step in series.
Claim 7
Dependent Claim
14 words
The method of claim 1 further including mechanical removal of portions of the mold.
Claim 8
Independent Claim
163 words
A method for making a molded refractory article comprising the steps of: providing a mold having a cavity therein corresponding to a master pattern substantially duplicating an article to be formed, the mold being formed using a stereolithographic or selective deposition modeling process; filling the mold cavity with a mixture comprising refractory particles in a liquid heat-fugitive binder; placing the mold and mixture in a furnace and raising the temperature within the furnace over a predetermined temperature and time schedule so as to cause, in order, a) the heat fugitive binder to cure to a solid, b) the mold to melt, oxidize, or reduce, leaving a molded refractory particle/binder article, c) the binder to leave the molded refractory particle/binder article to form a substantially binder free porous refractory article, and d) the refractory particles in the substantially binder free porous refractory article to adhere to provide a sintered porous molded refractory article; wherein said sintered porous molded refractory article duplicates the master pattern.
Claim 9
Independent Claim
163 words
A method for making a molded refractory article comprising the steps of: providing a mold having a cavity therein corresponding to a master pattern substantially duplicating an article to be formed, the mold being formed using a stereolithographic or selective deposition modeling process; filling the mold cavity with a mixture comprising refractory particles in a liquid heat-fugitive binder; placing the mold and mixture in a furnace and raising the temperature within the furnace over a predetermined temperature and time schedule so as to cause, in order, a) the heat fugitive binder to cure to a solid, b) the mold to melt, oxidize, or reduce, leaving a molded refractory particle/binder article, c) the binder to leave the molded refractory particle/binder article to form a substantially binder free porous refractory article, and d) the refractory particles in the substantially binder free porous refractory article to adhere to provide a sintered porous molded refractory article; wherein said sintered porous molded refractory article duplicates the master pattern.
Claim 10
Dependent Claim
31 words
The method of claim 7 which includes the additional step of infiltrating the sintered porous molded refractory article with a relatively low melting point molten metal infiltrant to fill the pores.
Claim 11
Independent Claim
108 words
A method for making an article comprising the steps of: providing a mold; disposing a master pattern within the mold to define a mold cavity; filling the mold cavity around the master pattern with a mixture comprising refractory particles and a heat fugitive binder to form a cast assembly; placing the cast assembly in a furnace, the furnace programmed to heat to preset temperatures over a fixed period of time, the preset temperatures held constant for a predetermined period of time; curing the mixture; separating the mold and master pattern from the cured mixture; removing the binder from the cured mixture; and sintering the binder free cured mixture.
Claim 12
Independent Claim
108 words
A method for making an article comprising the steps of: providing a mold; disposing a master pattern within the mold to define a mold cavity; filling the mold cavity around the master pattern with a mixture comprising refractory particles and a heat fugitive binder to form a cast assembly; placing the cast assembly in a furnace, the furnace programmed to heat to preset temperatures over a fixed period of time, the preset temperatures held constant for a predetermined period of time; curing the mixture; separating the mold and master pattern from the cured mixture; removing the binder from the cured mixture; and sintering the binder free cured mixture.
Claim 13
Dependent Claim
23 words
The method of claim 6 further including the step of infiltrating a molten metal into open spaces within the porous molded refractory article.
Claim 14
Dependent Claim
25 words
The method of claim 1 wherein the mixture is cured at about 30° to 40° C. for from about 16 hours to about 24 hours.
Claim 15
Dependent Claim
40 words
The method of claim 1 wherein the mold and cured mixture is heated to between about 50° C. to about 140° C. for about 30 minutes to about 60 minutes to remove the master pattern to leave a cured mold.
Claim 16
Dependent Claim
35 words
The method of claim 12 wherein the cured mold is heated to a temperature from about 850° C. to about 950° C. and held at that temperature for about 30 hours to about 45 hours.
Claim 17
Dependent Claim
55 words
The method of claim 1 wherein the porous sintered product is further heated to a temperature from about 900° C. to about 1150° C. for from about 20 minutes to about 250 minutes while the porous sintered product is in contact with a metal to cause the metal to infiltrate into the porous sintered product.
References Cited (Backward Citations)
US3823002A
Cited
US3929476A
Cited
US4431449A
Cited
US4373127A
Cited
US4469654A
Cited
US4327156A
Cited
US4455354A
Cited
US4491558A
Cited
US4554218A
Cited
US4844144A
Cited
US5507336A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-11-22 | 2003-05-24 | 2003-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-22 | 2007-05-24 | 2007-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-22 | 2011-05-24 | 2011-11-23 | $7700.00 | Window Closed / Lapsed |