US5012853A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making articles with smooth complex internal geometries
Assignee: Sundstrand Corp
•
Filing: 1988-09-20
•
Granted: 1991-05-07
•
Expires: 2008-09-20
Abstract
Abstract An improved process for forming objects such as turbine nozzles (10) with internal geometries without requiring machining of the internal geometry to produce a smooth complex internal surface (16, 18 and 19) is disclosed. The process includes forming a mandrel (30) containing a negative image of the internal geometry; coating the mandrel with a material (32) which is not chemically reactive with the material from which the mandrel is formed, capturing the mandrel in a mold or form (34) which is to receive the material from which the object is to be formed, the material (36) from which the object is to be made not being chemically reactive with the coating; filling the mold or form with the material to capture the mandrel and coating in solidified material contained in the form; and removing the form and the mandrel. If the material is a cast metal, the melting point of the material for forming the object should be below the melting point of the coating on the mandrel.
Inventors
- 👤 John A. Bihlmaier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 00:09
CPC Classifications
B; B22; B22D; B22D19/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49316; Y10T29/49428; Y10T29/49432
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
164 words
A process for making a turbine nozzle having a gas flow path with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a molten metal from which the turbine nozzle is to be cast, the molten metal from which the turbine nozzle is to be cast not being chemically reactive with the coating and having a melting point below the melting point of the material of the coating; filling the mold with molten casting metal to capture the mandrel and coating in solidified casting material contained in the mold; and removing the mold and the mandrel from the turbine nozzle while retaining the non-ferrous material as the gas flow path of the turbine nozzle.
Claim 2
Dependent Claim
164 words
A process for making a turbine nozzle having a gas flow path with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a molten metal from which the turbine nozzle is to be cast, the molten metal from which the turbine nozzle is to be cast not being chemically reactive with the coating and having a melting point below the melting point of the material of the coating; filling the mold with molten casting metal to capture the mandrel and coating in solidified casting material contained in the mold; and removing the mold and the mandrel from the turbine nozzle while retaining the non-ferrous material as the gas flow path of the turbine nozzle.
Claim 3
Dependent Claim
15 words
A process in accordance with claim 1 wherein: the coating on the mandrel is metallic.
Claim 4
Dependent Claim
35 words
A process for making castings in accordance with claim 2 wherein: the mandrel is made from a material which withstands compressive force upon cooling of the metal contained within the mold without damaging the mandrel.
Claim 5
Dependent Claim
17 words
A process for making castings in accordance with claim 3 wherein: the mandrel is made from carbon.
Claim 6
Dependent Claim
18 words
A process for making castings in accordance with claim 3 wherein: the mandrel is made from a ceramic.
Claim 7
Dependent Claim
19 words
A process for making castings in accordance with claim 3 wherein: the mandrel is made from a ceramic composite.
Claim 8
Dependent Claim
19 words
A process for making castings in accordance with claim 3 wherein: the mandrel is made from a soluble ceramic.
Claim 9
Dependent Claim
16 words
A process for making castings in accordance with claim 4 wherein: the mandrel is machined carbon.
Claim 10
Dependent Claim
22 words
A process for making castings in accordance with claim 2 wherein: the coating of the mandrel is placed by electroplating the mandrel.
Claim 11
Dependent Claim
22 words
A process for making castings in accordance with claim 2 wherein: the coating of the mandrel is placed by chemical vapor deposition.
Claim 12
Dependent Claim
22 words
A process for making castings in accordance with claim 2 wherein: the coating of the mandrel is placed by physical vapor deposition.
Claim 13
Dependent Claim
22 words
A process for making castings in accordance with claim 2 wherein: the coating of the mandrel is placed by thermal spray deposition.
Claim 14
Dependent Claim
158 words
A process for making a turbine nozzle having a gas flow path with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a material from which the turbine nozzle is to be formed, the material from which the turbine nozzle is to be formed not being chemically reactive with the coating; filling the form with the material from which the turbine nozzle is to be formed and processing the material to capture the mandrel and coating in the material contained in the form; and removing the form and the mandrel from the turbine nozzle while retaining the non-ferrous material as the gas flow path of the turbine nozzle.
Claim 15
Dependent Claim
158 words
A process for making a turbine nozzle having a gas flow path with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a material from which the turbine nozzle is to be formed, the material from which the turbine nozzle is to be formed not being chemically reactive with the coating; filling the form with the material from which the turbine nozzle is to be formed and processing the material to capture the mandrel and coating in the material contained in the form; and removing the form and the mandrel from the turbine nozzle while retaining the non-ferrous material as the gas flow path of the turbine nozzle.
Claim 16
Dependent Claim
19 words
A process for making formed objects in accordance with claim 13 wherein: the coating on the mandrel is metallic.
Claim 17
Dependent Claim
36 words
A process for making formed objects in accordance with claim 14 wherein: the mandrel is made from a material which withstands compressive force upon solidification of the material contained within the form without damaging the mandrel.
Claim 18
Dependent Claim
18 words
A process for making formed objects in accordance with claim 15 wherein: the mandrel is made from carbon.
Claim 19
Dependent Claim
19 words
A process for making formed objects in accordance with claim 15 wherein: the mandrel is made from a ceramic.
Claim 20
Dependent Claim
20 words
A process for making formed objects in accordance with claim 15 wherein: the mandrel is made from a ceramic composite.
Claim 21
Dependent Claim
20 words
A process for making formed objects in accordance with claim 15 wherein: the mandrel is made from a soluble ceramic.
Claim 22
Dependent Claim
17 words
A process for making formed objects in accordance with claim 16 wherein: the mandrel is machined carbon.
Claim 23
Dependent Claim
23 words
A process for making formed objects in accordance with claim 14 wherein: the coating of the mandrel is placed by electroplating the mandrel.
Claim 24
Dependent Claim
23 words
A process for making formed objects in accordance with claim 14 wherein: the coating of the mandrel is placed by chemical vapor deposition.
Claim 25
Dependent Claim
23 words
A process for making formed objects in accordance with claim 14 wherein: the coating of the mandrel is placed by physical vapor deposition.
Claim 26
Dependent Claim
23 words
A process for making formed objects in accordance with claim 14 wherein: the coating of the mandrel is placed by thermal spray deposition.
Claim 27
Dependent Claim
189 words
A process for making a casting with internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a molten metal from which the casting is to be cast, the molten metal from which the casting is to be cast not being chemically reactive with the coating and having a melting point below the melting point of the material of the coating; filling the mold with molten casting metal to capture the mandrel and coating in solidified casting material contained in the mold; removing the mold and the mandrel from the casting; and wherein the coating on the mandrel is chosen from a metal consisting of gold, silver, platinum, palladium, iridium, rhodium, rhenium, columbium, niobium, tantalum, chromium, tungsten and molybdenum; and the molten metal is chosen from the group consisting of stainless steel, nickel base alloys, superalloys, cobalt based alloys and aluminides.
Claim 28
Dependent Claim
189 words
A process for making a casting with internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a molten metal from which the casting is to be cast, the molten metal from which the casting is to be cast not being chemically reactive with the coating and having a melting point below the melting point of the material of the coating; filling the mold with molten casting metal to capture the mandrel and coating in solidified casting material contained in the mold; removing the mold and the mandrel from the casting; and wherein the coating on the mandrel is chosen from a metal consisting of gold, silver, platinum, palladium, iridium, rhodium, rhenium, columbium, niobium, tantalum, chromium, tungsten and molybdenum; and the molten metal is chosen from the group consisting of stainless steel, nickel base alloys, superalloys, cobalt based alloys and aluminides.
Claim 29
Dependent Claim
29 words
A process in accordance with claim 25 wherein: the casting is a turbine nozzle and the coating on the mandrel defines a gas flow path of the turbine nozzle.
Claim 30
Dependent Claim
170 words
A process for making a formed object with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a form which is to receive a material from which the object is to be formed, the material from which the object is to be formed not being chemically reactive with the coating; filling the form with the material from which the object is to be formed and processing the material to capture the mandrel and coating in the material contained in the form; removing the form and the mandrel from the object; and wherein the coating on the mandrel is chosen from a metal consisting of gold, silver, platinum, palladium, iridium, rhodium, rhenium, columbium, niobium, tantalum, chromium, tungsten and molybdenum; and the material is formed by powder metallurgical processing.
Claim 31
Dependent Claim
170 words
A process for making a formed object with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a form which is to receive a material from which the object is to be formed, the material from which the object is to be formed not being chemically reactive with the coating; filling the form with the material from which the object is to be formed and processing the material to capture the mandrel and coating in the material contained in the form; removing the form and the mandrel from the object; and wherein the coating on the mandrel is chosen from a metal consisting of gold, silver, platinum, palladium, iridium, rhodium, rhenium, columbium, niobium, tantalum, chromium, tungsten and molybdenum; and the material is formed by powder metallurgical processing.
Claim 32
Dependent Claim
29 words
A process in accordance with claim 27 wherein: the casting is a turbine nozzle and the coating on the mandrel defines a gas flow path of the turbine nozzle.
Claim 33
Dependent Claim
151 words
A process for making a castings with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a molten metal from which the casting is to be cast, the molten metal from which the casting is to be cast not being chemically reactive with the coating and having a melting point below the melting point of the material of the coating; filling the mold with molten casting metal to capture the mandrel and coating in solidified casting material contained in the form; and removing the form and the mandrel from the casting while retaining the non-ferrous material as the smooth internal surface.
Claim 34
Dependent Claim
151 words
A process for making a castings with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a molten metal from which the casting is to be cast, the molten metal from which the casting is to be cast not being chemically reactive with the coating and having a melting point below the melting point of the material of the coating; filling the mold with molten casting metal to capture the mandrel and coating in solidified casting material contained in the form; and removing the form and the mandrel from the casting while retaining the non-ferrous material as the smooth internal surface.
Claim 35
Dependent Claim
144 words
A process for making formed objects with an internal geometry with requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a form which is to receive a material from which the object is to be formed, the material from which the object is to be formed not being chemically reactive with the coating; filling the form with the material from which the object is to be formed and processing the material to capture the mandrel and coating in the material contained in the form; and removing the mold and the mandrel from the object while retaining the non-ferrous material as the smooth internal surface.
Claim 36
Dependent Claim
144 words
A process for making formed objects with an internal geometry with requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a form which is to receive a material from which the object is to be formed, the material from which the object is to be formed not being chemically reactive with the coating; filling the form with the material from which the object is to be formed and processing the material to capture the mandrel and coating in the material contained in the form; and removing the mold and the mandrel from the object while retaining the non-ferrous material as the smooth internal surface.
References Cited (Backward Citations)
DE242014C
Cited
US3072983A
Cited
GB1021880A
Cited
US3416591A
Cited
US3427698A
Cited
US3840185A
Cited
DE2404115A1
Cited
US3920064A
Cited
JPS5023327A
Cited
US3921701A
Cited
US3948309A
Cited
US3945423A
Cited
US4108931A
Cited
JPS534047A
Cited
JPS5311816A
Cited
US4043377A
Cited
JPS5429972A
Cited
US4137619A
Cited
US4185369A
Cited
EP0025481A1
Cited
JPS5736037A
Cited
US4370789A
Cited
US4532974A
Cited
US4447466A
Cited
US4569384A
Cited
US4574451A
Cited
JPS59169659A
Cited
US4559687A
Cited
EP0190114B1
Cited
US4642863A
Cited
US4603568A
Cited
US4712605A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-05-06 | 1994-11-05 | 1995-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-06 | 1998-11-05 | 1999-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-06 | 2002-11-05 | 2003-05-07 | $7700.00 | Window Closed / Lapsed |