US3854961A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of high temperature shell molds
Assignee: United Stirling AB and Co
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Filing: 1973-04-09
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Granted: 1974-12-17
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Expires: 1993-04-09
Abstract
Abstract An improved method for manufacturing shell molds which comprises coating a pattern with a binder composition containing a refractory metal and a zirconium compound, gelling the coated pattern and thereafter contacting the gelled coating with an acidified volatile organic solvent before applying subsequent coats. Latter backup coats which are made from a slurry containing hydrolyzed or partially hydrolyzed orthosilicates and refractory materials, may be gelled and treated with an acidified organic solvent.
Inventors
- 👤 J Flasch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:17
CPC Classifications
B; B22; B22C; B22C1/00; B22C1/16; B22C1/165; B22C9/00; B22C9/02; B22C9/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
143 words
IN A METHOD FOR PREPARING SHEEL MOLDS FOR PRECISION CASTING WHICH COMPRISES PRECOATING AN EXPENDABLE PATTERN WITH A SLURRY CONTAINING A REFRACTORY MATERIAL, A ZIRCONIUM COMPOUND AND AN ORGANIC SOLVENT, STUCCOING THE COATED PATTERN , CONTACTING THE COATED PATTERN WITH A GELLING AGENT SELECTED FROM THE CLASS CONSISTING OF AMMONIA AND AMINES HAVING UP TO 10 CARBON ATOMS AND THEREAFTER APPLYING A BACKUP COAT COMPRISING A REFRACTORY MATERIAL, AN ACID HYDROLYZED ORTHOSILICATE BINDER AND AN ORGANIC SOLVENT TO SAID PRECOAT, THE IMPROVEMENT WHICH COMPRISES CONTACTING SAID GELLED PRECOAT WITH AN ORGANIC SOLVENT HAVING A BOILING POINT BELOW ABOUT 250*C. AND CONTAINING SUFFICIENT ACID TO PROVIDE A HYDROGEN ION CONCENTRATION OF FROM 0.001 MOLE TO 0.1 MOLE PER LITER OF SOLVENT, SAID SOLVENT IS SELECTED FROM THE CLASS CONSISTING OF ALIPHATIC AND AROMATIC HYDROCARBONS CHLORINATED HYDROCARBONS, ALCOHOLS KETONES, ESTERS, ETHERS, GLYCOLS AND GLYCOL EHTERS.
Claim 2
Dependent Claim
143 words
IN A METHOD FOR PREPARING SHEEL MOLDS FOR PRECISION CASTING WHICH COMPRISES PRECOATING AN EXPENDABLE PATTERN WITH A SLURRY CONTAINING A REFRACTORY MATERIAL, A ZIRCONIUM COMPOUND AND AN ORGANIC SOLVENT, STUCCOING THE COATED PATTERN , CONTACTING THE COATED PATTERN WITH A GELLING AGENT SELECTED FROM THE CLASS CONSISTING OF AMMONIA AND AMINES HAVING UP TO 10 CARBON ATOMS AND THEREAFTER APPLYING A BACKUP COAT COMPRISING A REFRACTORY MATERIAL, AN ACID HYDROLYZED ORTHOSILICATE BINDER AND AN ORGANIC SOLVENT TO SAID PRECOAT, THE IMPROVEMENT WHICH COMPRISES CONTACTING SAID GELLED PRECOAT WITH AN ORGANIC SOLVENT HAVING A BOILING POINT BELOW ABOUT 250*C. AND CONTAINING SUFFICIENT ACID TO PROVIDE A HYDROGEN ION CONCENTRATION OF FROM 0.001 MOLE TO 0.1 MOLE PER LITER OF SOLVENT, SAID SOLVENT IS SELECTED FROM THE CLASS CONSISTING OF ALIPHATIC AND AROMATIC HYDROCARBONS CHLORINATED HYDROCARBONS, ALCOHOLS KETONES, ESTERS, ETHERS, GLYCOLS AND GLYCOL EHTERS.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein ammonia is used as the gelling agent.
Claim 4
Dependent Claim
16 words
The method of claim 1 wherein the precoat organic solvent is an alkylene glycol monoalkyl ether.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein the hydrolyzed orthosilicate is an alkyl silicate.
Claim 6
Dependent Claim
76 words
The method of claim 1 wherein the backup coat is contacted with a gelling agent and thereafter the gelled coating is treated with an organic solvent having a boiling point below about 250*C. and containing sufficient acid to provide a hydrogen ion concentration of from 0.0001 to 0.1 mole per liter of solvent, said solvent is selected from the class consisting of aliphatic and aromatic hydrocarbons, chlorinated hydrocarbons, alcohols, ketones, esters, ethers, glycols and glycol ethers.
Claim 7
Dependent Claim
14 words
The method of claim 1 wherein the zirconium compound is a hydrolyzed zirconium compound.
Claim 8
Dependent Claim
15 words
The method of claim 1 wherein the zirconium compound is a partially hydrolyzed zirconium compound.
Claim 9
Dependent Claim
12 words
The method of claim 1 wherein the precoat organic solvent is isopropanol.
Claim 10
Dependent Claim
29 words
The method of claim 1 wherein the sequence of steps is repeated until the desired precoat thickness is achieved and then the backup coat is applied over the precoat.
References Cited (Backward Citations)
US2945273A
Cited
US3455368A
Cited
US3392036A
Cited
US3537949A
Cited
US3616840A
Cited
US3752681A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |