Patent US4697632A successfully refreshed from Google Patents.
US4697632A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceramic porous bodies suitable for use with superalloys
Assignee: Howmet Corp
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Filing: 1982-06-11
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Granted: 1987-10-06
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Expires: 2002-06-11
Abstract
Abstract Ceramic porous bodies, including ceramic foam filters and smooth-faced ceramic objects, e.g., ceramic foam bricks, ceramic foam melting crucibles, and ceramic foam cores, made in accordance with the present invention are suitable for use with molten metal in general and molten superalloys in particular. The invention also provides a tundish for use with ceramic foam filters to filter metal en route from a metal furnace to a casting mold, and a melting device for use in casting metal which employs a ceramic foam filter as a bottom pour valve for a melting crucible such that the ceramic foam filter valve regulates the flow of molten metal therethrough in order to permit an entire ingot of metal to melt in the melting crucible before any metal begins to pour from the melting device into a casting mold.
Inventors
- 👤 Nick G. Lirones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:01
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B35/634; C04B35/63404; C04B35/63436; B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2068; B01D39/2093; B22; B22C; B22C9/00; B22C9/08; B22D; B22D11/00; B22D11/10; B22D11/11; B22D11/116; B22D11/119; C04B35/66; C04B38/00; C04B38/06; C04B38/0615; C04B41/00; C04B41/45; C04B41/50; C04B41/5025; C04B41/5035; C21; C21C; C21C7/00; C22; C22B; C22B9/00; C22B9/02; C22B9/023; B01D2239/00; B01D2239/04; B01D2239/0471; C04B2111/00; C04B2111/00474; C04B2111/00793; C04B2111/0087; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/32; C04B2235/3217; C04B2235/3231; C04B2235/3244; C04B2235/34; C04B2235/3418; Y; Y02; Y02P; Y02P10/00; Y02P10/20; Y10; Y10S; Y10S264/00; Y10S264/44
Claims Analysis
Total Claims: 68
Claim 1
Independent Claim
85 words
A process for making a ceramic foam filter suitable for use in filtering molten metals in general and molten superalloys in particular which comprises the steps of: providing an open-cell, flexible foam pattern; impregnating said foam pattern with a ceramic slurry; burning out said foam pattern at a temperature of between 1400° F. and 2200° F. to form a ceramic substrate; impregnating said ceramic substrate with additional ceramic slurry; and firing said impregnated ceramic substrate at a temperature of between 2200° F. and 3400° F.
Claim 2
Dependent Claim
85 words
A process for making a ceramic foam filter suitable for use in filtering molten metals in general and molten superalloys in particular which comprises the steps of: providing an open-cell, flexible foam pattern; impregnating said foam pattern with a ceramic slurry; burning out said foam pattern at a temperature of between 1400° F. and 2200° F. to form a ceramic substrate; impregnating said ceramic substrate with additional ceramic slurry; and firing said impregnated ceramic substrate at a temperature of between 2200° F. and 3400° F.
Claim 3
Dependent Claim
21 words
The process of claim 1 wherein the temperature at which said polyurethane foam pattern is burned out is about 1800° F.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein the temperature at which said impregnated ceramic substrate is fired is about 3100° F.
Claim 5
Dependent Claim
15 words
The process of claim 1 wherein said open-cell, flexible foam pattern is a polyurethane foam.
Claim 6
Dependent Claim
27 words
The process of claim 1 wherein said polyurethane foam is a reticulated, fully open-pore, flexible, ester type, polyurethane foam having between 10 and 30 pores per inch.
Claim 7
Dependent Claim
100 words
The process of claim 1 wherein the step of impregnating said foam pattern with a ceramic slurry includes the steps of dipping said foam pattern into a ceramic slurry dipcoat, draining excess slurry from said pattern, drying said foam pattern, redipping said foam pattern into said ceramic slurry dipcoat, draining excess slurry from said foam pattern without squeezing, and drying said foam pattern; and the step of impregnating said ceramic substrate with additional ceramic slurry includes the steps of dipping said ceramic substrate into said ceramic slurry dipcoat, draining excess slurry from said ceramic substrate, and drying said ceramic substrate.
Claim 8
Dependent Claim
20 words
The process of claim 6 wherein said redipping, draining and drying of said foam pattern is repeated at least once.
Claim 9
Dependent Claim
57 words
The process of claim 6 wherein said ceramic slurry dipcoat has a composition of between 1% and 20% silica by weight (dry basis) and between 99% and 80% alumina by weight (dry basis), a viscosity of between 5 and 20 seconds, and a film weight of between 1.0 and 8.0 grams per standard six inch square plate.
Claim 10
Dependent Claim
51 words
The process of claim 8 wherein said ceramic slurry dipcoat comprises about 9.2% silica by weight (dry basis) and about 90.8% alumina by weight (dry basis), has a viscosity of between 10 and 13 seconds, and a film weight of between 3.7 and 4.0 grams per standard six inch square plate.
Claim 11
Dependent Claim
20 words
The process of claim 8 wherein said silica is aqueous colloidal silica and said alumina is -325 mesh alumina flour.
Claim 12
Dependent Claim
23 words
The process of claim 8 wherein said ceramic slurry dipcoat composition also includes a suspending agent, a wetting agent and a defoaming agent.
Claim 13
Dependent Claim
27 words
The process of claim 11 wherein said suspending agent is polyvinyl chloride latex, said wetting agent is an organic phosphate ester, and said defoaming agent is ethylhexanol.
Claim 14
Dependent Claim
60 words
The process of claim 1 wherein the step of impregnating said foam pattern with a ceramic slurry includes the step of dipping said foam pattern into a ceramic slurry prewet and a ceramic slurry dipcoat, and the step of impregnating said ceramic substrate with additional ceramic slurry includes the step of dipping said ceramic substrate into said ceramic slurry prewet.
Claim 15
Dependent Claim
121 words
The process of claim 13 wherein said step of dipping said foam pattern into a ceramic slurry prewet and a ceramic slurry dipcoat includes the steps of dipping said foam pattern into said ceramic slurry prewet, draining excess slurry from said foam pattern, dipping said foam pattern into said ceramic slurry dipcoat, draining excess slurry from said foam pattern, drying said foam pattern, redipping said foam pattern into said ceramic slurry prewet, draining excess slurry from said foam pattern without squeezing, redipping said foam pattern into said ceramic slurry dipcoat, draining excess slurry from said foam pattern without squeezing and drying said foam pattern, said redipping into prewet, draining, redipping into dipcoat, draining and drying steps being repeated at least once.
Claim 16
Dependent Claim
94 words
The process of claim 13 wherein said ceramic slurry dipcoat has a composition of between 1% and 20% silica by weight (dry basis) and between 99% and 80% alumina by weight (dry basis), a viscosity of between 5 and 60 seconds, and a film weight of between 1.0 and 8.0 grams per standard six inch square plate, and said ceramic slurry prewet has a composition of between 1% and 30% silica by weight (dry basis) and between 99% and 70% alumina by weight (dry basis), and a viscosity of between 1 and 25 seconds.
Claim 17
Dependent Claim
82 words
The process of claim 15 wherein said ceramic slurry dipcoat comprises about 9.2% silica by weight (dry basis) and about 90.8% alumina by weight (dry basis), has a viscosity of between 24 and 30 seconds, and a film weight of between 4.5 and 5.5 grams per standard six inch square plate, and said ceramic slurry prewet comprises about 11.9% silica by weight (dry basis) and about 88.1% alumina by weight (dry basis), and has a viscosity of between 8 and 10 seconds.
Claim 18
Dependent Claim
20 words
The process of claim 15 wherein said silica is aqueous colloidal silica and said alumina is -325 mesh alumina flour.
Claim 19
Dependent Claim
27 words
The process of claim 15 wherein said ceramic slurry dipcoat and said ceramic slurry prewet also include a suspending agent, a wetting agent and a defoaming agent.
Claim 20
Dependent Claim
27 words
The process of claim 18 wherein said suspending agent is polyvinyl chloride latex, said wetting agent is an organic phosphate ester, and said defoaming agent is ethylhexanol.
Claim 21
Dependent Claim
102 words
The process of claim 13 wherein said ceramic slurry dipcoat has a composition of between 1% and 20% colloidal silica solids by weight (dry basis) and between 99% and 80% fused silica solids by weight (dry basis), a viscosity of between 10 and 80 seconds, and a film weight of between 1 and 14 grams per standard six inch square plate, and said ceramic slurry preset has a composition of between 1% and 30% colloidal silica solids by weight (dry basis) and between 99% and 70% fused silica solids by weight (dry basis), and a viscosity of between 1 and 25 seconds.
Claim 22
Dependent Claim
90 words
The process of claim 20 wherein said ceramic slurry dipcoat comprises about 12.4% colloidal silica solids by weight (dry basis) and about 87.6% fused silica solids by weight (dry basis), has a viscosity of between 40 and 50 seconds, and a film weight of between 5 and 7 grams per standard six inch square plate, and said ceramic slurry prewet comprises about 24.8% colloidal silica solids by weight (dry basis) and about 75.2% fused silica solids by weight (dry basis), and has a viscosity of between 6 and 8 seconds.
Claim 23
Dependent Claim
15 words
The process of claim 20 wherein said fused silica solid is -325 mesh silica flour.
Claim 24
Dependent Claim
29 words
The process of claim 20 wherein said ceramic slurry dipcoat composition and said ceramic slurry prewet composition also include a suspending agent, a wetting agent and a defoaming agent.
Claim 25
Dependent Claim
27 words
The process of claim 23 wherein said suspending agent is polyvinyl chloride latex, said wetting agent is an organic phosphate ester, and said defoaming agent is ethylhexanol.
Claim 26
Dependent Claim
60 words
The process of claim 1 wherein the step of impregnating said ceramic substrate with additional ceramic slurry includes the steps of dipping said ceramic slurry into a post-burnout ceramic slurry dipcoat, draining excess slurry from said ceramic substrate, and drying said ceramic substrate, said post-burnout ceramic slurry dipcoat comprising zirconia and having a viscosity of between 1 and 20 seconds.
Claim 27
Dependent Claim
12 words
The process of claim 25 wherein said viscosity is about 5 seconds.
Claim 28
Dependent Claim
12 words
The process of claim 25 wherein said zirconia is -325 mesh zirconia.
Claim 29
Dependent Claim
21 words
The process of claim 25 wherein said post-burnout ceramic slurry dipcoat also includes a polyelectrolyte dispersing agent and a suspending agent.
Claim 30
Dependent Claim
12 words
The process of claim 28 wherein said suspending agent is citric acid.
Claim 31
Dependent Claim
60 words
The process of claim 1 wherein the step of impregnating said ceramic substrate with additional ceramic slurry includes the steps of dipping said ceramic slurry into a post-burnout ceramic slurry dipcoat, draining excess slurry from said ceramic substrate, and drying said ceramic substrate, said post-burnout ceramic slurry dipcoat comprising alumina and having a viscosity of between 1 and 20 seconds.
Claim 32
Dependent Claim
12 words
The process of claim 31 wherein said viscosity is about 7 seconds.
Claim 33
Dependent Claim
27 words
The process of claim 30 wherein said alumina has an ultimate crystal size of between 3.0 and 3.5 μm and an alumina content of greater than 99.5%.
Claim 34
Dependent Claim
21 words
The process of claim 30 wherein said post-burnout ceramic slurry dipcoat also includes a polyelectrolyte dispersing agent and a suspending agent.
Claim 35
Dependent Claim
12 words
The process of claim 33 wherein said suspending agent is citric acid.
Claim 36
Dependent Claim
26 words
A ceramic foam filter useful as a filtering material for molten metal in general and molten superalloys in particular made by the process of claim 1.
Claim 37
Dependent Claim
26 words
A ceramic foam filter useful as a filtering material for molten metal in general and molten superalloys in particular made by the process of claim 8.
Claim 38
Dependent Claim
26 words
A ceramic foam filter useful as a filtering material for molten metal in general and molten superalloys in particular made by the process of claim 15.
Claim 39
Dependent Claim
26 words
A ceramic foam filter useful as a filtering material for molten metal in general and molten superalloys in particular made by the process of claim 20.
Claim 40
Dependent Claim
26 words
A ceramic foam filter useful as a filtering material for molten metal in general and molten superalloys in particular made by the process of claim 25.
Claim 41
Dependent Claim
26 words
A ceramic foam filter useful as a filtering material for molten metal in general and molten superalloys in particular made by the process of claim 30.
Claim 42
Dependent Claim
185 words
A process for making a ceramic porous body suitable for use with molten metals in general and molten superalloys in particular having a solid, high density, high purity, smooth face which comprises the steps of: providing an open-cell, flexible, foam pattern and a face pattern the size of a face of said foam pattern to be smoothed; coating said face pattern with a ceramic slurry; stuccoing said face pattern with a coarse ceramic material; impregnating said foam pattern with said ceramic slurry; placing said impregnated foam pattern on said coated, stuccoed face pattern such that said impregnated foam pattern and said coated, stuccoed face pattern dry together and become attached; impregnating said attached impregnated foam pattern and coated, stuccoed face pattern with additional ceramic slurry; removing excess dried ceramic down to the edges of said foam pattern; burning out said foam pattern and said face pattern at a temperature of between 1400° F. and 2200° F. to form a ceramic substrate; impregnating said ceramic substrate with additional ceramic slurry; and firing said impregnated ceramic substrate at a temperature of between 2200° F. and 3400° F.
Claim 43
Dependent Claim
185 words
A process for making a ceramic porous body suitable for use with molten metals in general and molten superalloys in particular having a solid, high density, high purity, smooth face which comprises the steps of: providing an open-cell, flexible, foam pattern and a face pattern the size of a face of said foam pattern to be smoothed; coating said face pattern with a ceramic slurry; stuccoing said face pattern with a coarse ceramic material; impregnating said foam pattern with said ceramic slurry; placing said impregnated foam pattern on said coated, stuccoed face pattern such that said impregnated foam pattern and said coated, stuccoed face pattern dry together and become attached; impregnating said attached impregnated foam pattern and coated, stuccoed face pattern with additional ceramic slurry; removing excess dried ceramic down to the edges of said foam pattern; burning out said foam pattern and said face pattern at a temperature of between 1400° F. and 2200° F. to form a ceramic substrate; impregnating said ceramic substrate with additional ceramic slurry; and firing said impregnated ceramic substrate at a temperature of between 2200° F. and 3400° F.
Claim 44
Dependent Claim
132 words
The process of claim 41 wherein the step of impregnating said attached impregnated foam pattern and coated stuccoed face pattern with additional ceramic slurry includes the steps of dipping said attached foam pattern and face pattern into a ceramic slurry dipcoat, draining excess slurry from said attached foam pattern and face pattern, drying said attached foam pattern and face pattern, redipping said attached foam pattern and face pattern into said ceramic slurry dipcoat, draining excess slurry from said attached foam pattern and face pattern without squeezing, and drying said attached foam pattern and face pattern; and the step of impregnating said ceramic substrate with additional ceramic slurry includes the steps of dipping said ceramic substrate into said ceramic slurry dipcoat, draining excess slurry from said ceramic substrate, and drying said ceramic substrate.
Claim 45
Dependent Claim
57 words
The method of claim 41 wherein said ceramic slurry dipcoat has a composition of between 1% and 20% silica by weight (dry basis) and between 99% and 80% alumina by weight (dry basis), a viscosity of between 5 and 20 seconds, and a film weight of between 1.0 and 8.0 grams per standard six inch square plate.
Claim 46
Dependent Claim
71 words
The method of claim 41 wherein the step of impregnating said attached impregnated foam pattern and coated, stuccoed face pattern with additional ceramic slurry includes the step of dipping said attached foam pattern and face pattern into a ceramic slurry prewet and a ceramic slurry dipcoat, and the step of impregnating said ceramic substrate with additional ceramic slurry includes the step of dipping said ceramic substrate into said ceramic slurry prewet.
Claim 47
Dependent Claim
94 words
The method of claim 44 wherein said ceramic slurry dipcoat has a composition of between 1% and 20% silica by weight (dry basis) and between 99% and 80% alumina by weight (dry basis), a viscosity of between 5 and 60 seconds, and a film weight of between 1.0 and 8.0 grams per standard six inch square plate, and said ceramic slurry prewet has a composition of between 1% and 30% silica by weight (dry basis) and between 99% and 70% alumina by weight (dry basis), and a viscosity of between 1 and 25 seconds.
Claim 48
Dependent Claim
102 words
The method of claim 44 wherein said ceramic slurry dipcoat has a composition of between 1% and 20% colloidal silica solids by weight (dry basis) and between 99% and 80% fused silica solids by weight (dry basis), a viscosity of between 10 and 80 seconds, and a film weight of between 1 and 14 grams per standard six inch square plate, and said ceramic slurry prewet has a composition of between 1% and 30% colloidal silica solids by weight (dry basis) and between 99% and 70% fused silica solids by weight (dry basis), and a viscosity of between 1 and 25 seconds.
Claim 49
Dependent Claim
60 words
The process of claim 41 wherein the step of impregnating said ceramic substrate with additional ceramic slurry includes the steps of dipping said ceramic slurry into a post-bur-out ceramic slurry dipcoat, draining excess slurry from said ceramic substrate, and drying said ceramic substrate, said post-burn-out ceramic slurry dipcoat comprising zirconia and having a viscosity of between 1 and 20 seconds.
Claim 50
Dependent Claim
60 words
The process of claim 41 wherein the step of impregnating said ceramic substrate with additional ceramic slurry includes the steps of dipping said ceramic slurry into a post-burn-out ceramic slurry dipcoat, draining excess slurry from said ceramic substrate, and drying said ceramic substrate, said post-burn-out ceramic slurry dipcoat comprising alumina and having a viscosity of between 1 and 20 seconds.
Claim 51
Dependent Claim
34 words
Insulating refractory lining for large metal melting furnaces and ladles suitable for use with molten metal in general and molten superalloys in particular comprising ceramic porous bodies made by the process of claim 41.
Claim 52
Dependent Claim
34 words
Insulating refractory lining for large metal melting furnaces and ladles suitable for use with molten metals in general and molten superalloys in particular comprising ceramic porous bodies made by the process of claim 43.
Claim 53
Dependent Claim
34 words
Insulating refractory lining for large metal melting furnaces and ladles suitable for use with molten metals in general and molten superalloys in particular comprising ceramic porous bodies made by the process of claim 45.
Claim 54
Dependent Claim
34 words
Insulating refractory lining for large metal melting furnaces and ladles suitable for use with molten metals in general and molten superalloys in particular comprising ceramic porous bodies made by the process of claim 46.
Claim 55
Dependent Claim
34 words
Insulating refractory lining for large metal melting furnaces and ladles suitable for use with molten metals in general and molten superalloys in particular comprising ceramic porous bodies made by the process of claim 47.
Claim 56
Dependent Claim
34 words
Insulating refractory lining for large metal melting furnaces and ladles suitable for use with molten metals in general and molten superalloys in particular comprising ceramic porous bodies made by the process of claim 48.
Claim 57
Dependent Claim
39 words
A melting crucible suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, internal face, comprising a ceramic porous body made from the method of claim 41.
Claim 58
Dependent Claim
39 words
A melting crucible suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, internal face, comprising a ceramic porous body made from the method of claim 43.
Claim 59
Dependent Claim
39 words
A melting crucible suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, internal face, comprising a ceramic porous body made from the method of claim 45.
Claim 60
Dependent Claim
39 words
A melting crucible suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, internal face, comprising a ceramic porous body made from the method of claim 46.
Claim 61
Dependent Claim
39 words
A melting crucible suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, internal face, comprising a ceramic porous body made from the method of claim 47.
Claim 62
Dependent Claim
39 words
A melting crucible suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, internal face, comprising a ceramic porous body made from the method of claim 48.
Claim 63
Dependent Claim
38 words
A ceramic core suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, exterior face, comprising a ceramic body made from the process of claim 41.
Claim 64
Dependent Claim
38 words
A ceramic core suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, exterior face, comprising a ceramic body made from the process of claim 43.
Claim 65
Dependent Claim
38 words
A ceramic core suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, exterior face, comprising a ceramic body made from the process of claim 45.
Claim 66
Dependent Claim
38 words
A ceramic core suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, exterior face, comprising a ceramic body made from the process of claim 46.
Claim 67
Dependent Claim
38 words
A ceramic core suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purity, smooth, exterior face, comprising a ceramic body made from the process of claim 47.
Claim 68
Dependent Claim
38 words
A ceramic core suitable for use with molten metals in general and molten superalloys in particular and having a solid, high density, high purrity, smooth, exterior face, comprising a ceramic body made from the process of claim 48.
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| 7.5 Years (Year 8) | 1994-10-05 | 1995-04-06 | 1995-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-05 | 1999-04-06 | 1999-10-06 | $7700.00 | Window Closed / Lapsed |