US3789096A
Expired / Lapsed
US
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Method of impregnating porous refractory bodies with inorganic chromium compound
Assignee: Kaman Sciences Corp
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Filing: 1967-12-28
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Granted: 1974-01-29
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Expires: 1987-12-28
Abstract
Abstract A new ceramic treatment process and product and, more particularly, a process for forming and treating and shaping and treating of porous skeletal bodies to produce hardened dimensionally stable end products at relatively low temperature and the resulting materials produced thereby which comprises the steps of treating a porous skeletal body by impregnating the interstices of the porous body with a comound of a metal capable of being converted to an oxide in situ at relatively low temperatures, heating the body so impregnated at temperature well below normal vitrification to a temperature of at least 600*F. and for a period of time sufficient to convert the compound impregnated therein to an oxide and repeating the impregnation and heating steps until the desired degree of hardness is obtained.
Inventors
- 👤 P Church
- 👤 O Knutson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:07
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/45; C04B41/50; C04B41/5025; C04B41/5033; C04B41/009; C04B41/80; C04B41/81; C04B41/85; C04B41/87; C09; C09K; C09K3/00; C09K3/14; C09K3/1436; F; F02; F02B; F02B75/00; F02B75/02; F02B2075/022; F02B2075/027
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
56 words
The method of claim 1 wherein at least the surface of the particles are selected from the group of inorganic refractories consisting of oxides of aluminum, barium, beryllium, calcium, cerium, chromium, cobalt, copper, gallium, hafnium, iron, lanthanum, magnesium, manganese, molybdenum, nickel, niobium, silicon, tantalum, thorium, tin, titanium, tungsten, uranium, vanadium, yttrium, zinc, zirconium and mixtures thereof.
Claim 2
Dependent Claim
11 words
The method of claim 1 wherein the solution is chromic acid.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein the finely divided refractory particles include an amount of reinforcing fibers, which fibers retain their identity even in the fully hardened body.
Claim 4
Dependent Claim
63 words
The method of claim 1 which includes as a last step the impregnation of the hardened refractory body with phosphoric acid and heating and curing said body by raising the temperature of said body to at least about 600*F. but below the vitrification temperature of the refractory particles in increments over a period of time sufficient to completely dry and harden the body.
Claim 5
Dependent Claim
38 words
The method of claim 1 wherein a clay or inorganic chromium compound binder is mixed with the finely divided particles prior to forming the structure which serves to hold the particles together during the impregnation and curing cycles.
Claim 6
Independent Claim
138 words
A method of producing a chemically hardened refractory body which comprises: closely packing finely divided discrete refractory oxide particles having a vitrification temperature in excess of 600*F. to form a porous body essentially devoid of vitreous bonding between the particles; impregnating said porous body with a solution of an inorganic chromium compound in a solvent selected from the group consisting of water, alcohol and ether, which compound is capable of being converted to an oxide on being heated to a temperature below the vitrification temperature of said refractory oxide particles; drying and curing said impregnated body by heating same to a temperature below the vitrification temperature of the particles but sufficient to convert the chromium compound in situ to the oxide; and, repeating the impregnation and heat curing steps at least once to harden and densify the body.
Claim 7
Dependent Claim
26 words
The method of claim 7 wherein the oxide particles are packed into a mold of predetermined shape at least during the initial impregnation and cure steps.
Claim 8
Dependent Claim
39 words
The method of claim 7 wherein the oxide particles are mixed with a clay or inorganic chromium compound binder to provide a plastic mass which is formed into a predetermined shape prior to the initial impregnation and cure steps.
Claim 9
Dependent Claim
48 words
The method of claim 7 wherein the particles are selected from the group consisting of oxides of aluminum, barium, beryllium, calcium, cerium, chromium, cobalt, copper, gallium, hafnium, iron, lanthanum, magnesium, manganese, molybdenum, nickel, niobium, silicon, tantalum, thorium, tin, titanium, tungsten, uranium, vanadium, yttrium, zinc, zirconium and mixtures thereof.
Claim 10
Dependent Claim
11 words
The method of claim 7 wherein the solution is chromic acid.
Claim 11
Dependent Claim
28 words
The method of claim 7 wherein the finely divided refractory particles include an amount of reinforcing fibers, which fibers retain their identity even in the fully hardened body.
Claim 12
Dependent Claim
54 words
The method of claim 7 which includes as a last step the impregnation of the hardened refractory body with phosphoric acid and heating and curing said body by raising the temperature of said body to at least about 600*F. in increments over a perioD of time sufficient to completely dry and harden the body.
Claim 13
Independent Claim
127 words
A method of producing a chemically hardened refractory body which comprises: providing a non-vitrified porous skeletal core of inorganic refractory material having a vitrification temperature in excess of 600*F.; impregnating said core with a solution of an inorganic chromium compound in a solvent selected from the group consisting of water, alcohol and ether which compound is capable of being converted to an oxide on being heated to a temperature below the vitrification temperature of said refractory material; drying and curing said impregnated core by heating the core to a temperature below the vitrification temperature of said refractory material but sufficient to convert the chromium compound to the oxide in situ; and, repeating the impregnation and heat curing steps at least once to harden and densify the core.
Claim 14
Dependent Claim
51 words
The method of claim 14 wherein the skeletal core is of a material from the group consisting of oxides of aluminum, barium, beryllium, calcium, cerium, chromium, cobalt, copper, gallium, hafnium, iron, lanthanum, magnesium, manganese, molybdenum, nickel, niobium, silicon, tantalum, thorium, tin, titanium, tungsten, uranium, vanadium, yttrium, zinc, zirconium and mixtures thereof.
Claim 15
Dependent Claim
11 words
The method of claim 14 wherein the solution is chromic acid.
Claim 16
Dependent Claim
63 words
The method of claim 14 which includes as a last step the impregnation of the hardened refractory body with phosphoric acid and heating and curing said body by raising the temperature of said body to a least about 600*F. but below the vitrification temperature of the refractory particles in increments over a period of time sufficient to completely dry and harden the body.
Claim 17
Dependent Claim
22 words
The method of claim 6 wherein the clay binder is selected from the group consisting of bentonite, kaolin and Kentucky ball clays.
Claim 18
Dependent Claim
11 words
The method of claim 6 wherein the binder is chromic acid.
Claim 19
Dependent Claim
22 words
The method of claim 9 wherein the clay binder is selected from the group consisting of bentonite, kaolin and Kentucky ball clays.
Claim 20
Dependent Claim
11 words
The method of claim 7 wherein the binder is chromic acid.
Claim 21
Dependent Claim
55 words
A method according to claim 7 wherein the finely divided oxide particles are pretreated with a solution of a inorganic chromium compound capable of being converted to an oxide on being heated and the particles are heated to convert the treating solution thereon to an oxide before being closely packed to form a porous structure.
Claim 22
Dependent Claim
55 words
A method according to claim 10 wherein the finely divided oxide particles are pretreated with a solution of a inorganic chromium compound capable of being converted to an oxide on being heated and the particles are heated to convert the treating solution thereon to an oxide before being closely packed to form a porous structure.
Claim 23
Dependent Claim
13 words
The method of claim 1 wherein the finely divided particles are metal particles.
Claim 24
Dependent Claim
13 words
The method of claim 1 wherein the finely divided particles are carbide particles.
Claim 25
Dependent Claim
13 words
The method of claim 1 wherein the finely divided particles are complex oxides.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |