EP0451467A1 - Méthode de frittage utilisant un moule déformable en céramique - Google Patents
Méthode de frittage utilisant un moule déformable en céramique Download PDFInfo
- Publication number
- EP0451467A1 EP0451467A1 EP91102428A EP91102428A EP0451467A1 EP 0451467 A1 EP0451467 A1 EP 0451467A1 EP 91102428 A EP91102428 A EP 91102428A EP 91102428 A EP91102428 A EP 91102428A EP 0451467 A1 EP0451467 A1 EP 0451467A1
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- European Patent Office
- Prior art keywords
- mold
- component
- ceramic
- powder
- sintering
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/1208—Containers or coating used therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/1208—Containers or coating used therefor
- B22F3/1216—Container composition
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/1208—Containers or coating used therefor
- B22F3/1258—Container manufacturing
- B22F3/1283—Container formed as an undeformable model eliminated after consolidation
Definitions
- the invention relates to the further development, perfection and simplification of powder metallurgical manufacturing methods for the production of workpieces with comparatively complicated shapes, where the problems of shrinkage during sintering play an important role.
- the main area of application is in the area of components for turbine construction.
- the invention relates to a method for shaping any component from a metallic and / or ceramic material, starting from a powder or a powder mixture, the powder being poured loosely into a mold and then subjected to a sintering process.
- the invention has for its object to provide a method with which, starting from metal or ceramic powders, a comparatively complicated shaped workpiece of any cross-section and unlimited wall thickness can be produced.
- the process is intended to provide a reproducible finished product that no longer has to be processed, or at most only slightly. When processing powder bubbles and unwanted harmful residues should be avoided.
- the process is intended to ensure the greatest possible freedom of movement and universality.
- a flexible ceramic body is used as the mold, which yields elastically and / or plastically under the stresses that occur due to expansion or shrinkage due to expansion or shrinkage and cause tensile and / or compressive forces, and / or tears at targeted breaking points, but its strength and dimensional stability over the entire temperature range and over the entire process sequence is sufficiently high to ensure high dimensional accuracy of the component to be manufactured as a sintered body.
- FIG. 1 shows a flow diagram (block diagram) of the method using an elastic / plastically yielding form.
- the diagram needs no further explanation.
- the shape is made of a resilient material and is designed to accommodate the movements of the sintered body to be produced follows without tearing or breaking.
- FIG. 2 shows a flow diagram (block diagram) of the method using a flexible form with predetermined breaking points.
- the shape here consists of a material that breaks at certain points as soon as the body to be sintered has sufficient inherent strength. The shape which is broken or torn in this way then no longer offers any appreciable resistance to the solidifying sintered body, so that it can expand or contract in all directions without being severely prevented.
- this category of form includes all variants in which the form undergoes more or less irreversible changes during the sintering process of the workpiece: the form tears, breaks, disintegrates, is at least locally crushed, etc.
- the shape need not necessarily have precisely predisposed predetermined breaking points as notches, grooves, etc.
- the "predetermined breaking point" can also occur arbitrarily anywhere where the strength of the material is exceeded. After the sintering process, the destroyed form is not ready for use again.
- Fig. 3 relates to a schematic elevation / section of a yielding split mold with powder filling for the purpose of demonstrating the principle of conformity when shrinking: state before shrinking.
- 1 represents the powder filling (powder filling) for the component.
- 2 is a yielding split mold made of ceramic material in the state before the component shrinks (heat treatment, sintering process).
- 4 shows a schematic elevation / section of a yielding split mold with a sintered body for the purpose of demonstrating the principle of conformity during shrinking: state during shrinking (even after the shrinking process has ended during the sintering process).
- 3 is the solidifying sintered body (component, workpiece) formed from the powder in the meantime.
- 4 shows the yielding split form made of ceramic material during and after the shrinking of the component.
- the shrinkage is only shown in the direction of the main longitudinal axis, while that in the transverse direction has not been taken into account.
- the direction of movement during the shrinking process of the component is indicated by opposite vertical arrows. These arrows also represent the longitudinal compression forces acting on the ceramic mold. The mold is thus compressed in the present case.
- 5 is the original contour (dashed line) of the yielding shape before the component shrinks (see FIG. 3).
- FIG. 5 shows a schematic elevation / section of a yielding split mold and a finished sintered body for the purpose of demonstrating the principle of conformity during shrinking: state after removal of the filled mold.
- 3 is the sintered body
- 6 the divided form made of ceramic material after its removal. After releasing the tension, the elastic shape (in this case two halves) almost returns to its original shape.
- the arrows show the direction of movement of the molded parts as they are removed from the workpiece.
- FIG. 6 shows a schematic elevation / section of a detail from a yielding form for the purpose of demonstrating the principle of the predetermined breaking point during shrinking.
- 7 is any section of a compliant shape made of ceramic material. This stylized example can be easily applied to the case of the side limitation transferred to a turbine blade with cantilevered head and foot sections.
- 8 represents an expansion piece (bulge, bulge) of the yielding shape. This section serves to deflect the forces (pressure forces p) and to generate a bending moment (M b ) at the predetermined breaking point 9, which is subjected to bending when the component shrinks. In addition, such a bulge provides the space for the movement of the mold caused by the shrinkage of the component.
- FIG. 7 relates to a schematic elevation / section of a yielding shape with predetermined breaking points and a powder filling: state before shrinking.
- 1 is the powder filling for the component, 10 the yielding undivided form made of ceramic material with predetermined breaking points before the component shrinks.
- 8 is an expansion piece in the form of a parabolic bulge with predetermined breaking point 9 in the form of a notch (groove) 11. The space enveloped by expansion piece 8 is closed off from the workpiece side by an elastic-plastic ceramic seal 12 in the manner of a fleece or felt or flexible fiber product.
- FIG. 8 shows a schematic elevation / section of a yielding shape with broken predetermined breaking points and a sintered body: state during shrinking during sintering.
- 3 is the sintered body, shown shrunk in the longitudinal direction compared to the powder filling 1 (FIG. 7).
- 9 is a predetermined breaking point (shape already broken).
- 13 is a part of the yielding undivided shape made of ceramic material during and after the shrinking of the component.
- 12 is the elastic-plastic ceramic seal, which has been squeezed here in part by compressing it into the space available transversely.
- 14 shows a crack in a part of the form made of ceramic material during and after the component has shrunk. In the present case, the crack 14 gapes at this point due to high bending moments. If the shrinkage is severe, they break cantilevered expansion pieces (8 in Fig. 7) completely or are even crushed.
- FIG. 9 shows a schematic elevation / section of a yielding shape with broken predetermined breaking points and a finished sintered body: state after the fragments of the cracked shape have been removed.
- 3 is the sintered body, 12 the elastic-plastic ceramic seal and 15 each a fragment of the yielding shape made of ceramic material after removal.
- 16 is an irregular fracture surface at the predetermined breaking point of the mold.
- the crack 14 in a fragment is shown closed after the bending moment ceases to exist. In contrast, the lowest fragments 15 are completely broken through. There are all variants of the destroyed form.
- the arrows indicate the direction of movement of the fragments 15 when they are removed from the component to be manufactured.
- Fig. 10 shows a schematic elevation / section of a thin-walled yielding shape with numerous notches as predetermined breaking points and a powder filling: state before shrinking.
- the reference numerals basically correspond to those of FIG. 7.
- the wall thickness of the mold 10 is greatly reduced compared to FIG. 5.
- the notches 11 of the predetermined breaking points have a parabolic profile and are predominantly located at the thickened corners of the mold 10. As a result, bending moments are generated during the shrinking, which cause the shell-like mold 10 to break open.
- 11 relates to a schematic section of a detail from a mold consisting of several ceramic layers and a sintered body.
- the detail shows a sintered body 3 at the location of a rib with a rectangular cross section.
- the mold in the present case represents a shell-like body made of different layers.
- 17 is a smooth inner skin of the mold made of ceramic material. This is usually done with a fine-grained mass, Paste (slip, etc.) used.
- 18 is the essentially shape-determining, medium-fine-grained inner layer (shell) of the form made of ceramic material. Their relatively dense grains are drawn as more or less globular particles.
- 19 is the coarse-grained middle layer (shell) of the form. 20 represents the coarse-pored, framework-like outer layer of the mold.
- FIG. 12 shows a schematic section of a section from a mold consisting of a highly porous foam ceramic layer and a mechanically stronger glass ceramic layer and a sintered body: state before cracking during sintering.
- the smooth inner skin 17 made of ceramic material.
- 21 is an inner layer (shell) of the form made of highly porous foam ceramic. The latter has coarse through pores 22.
- 23 represents an outer layer (shell) of the form made of glass ceramic (fiber-reinforced).
- FIG. 13 shows a schematic section of a detail from a mold consisting of a highly porous foam ceramic layer and a glass ceramic layer and a sintered body: state after tearing and crumbling.
- the reference numerals 3, 17, 21, 22, 23 are exactly the same as in Fig. 12.
- 24 is a crack in the foam ceramic of the mold, which is approximately perpendicular to the workpiece surface (sintered body 3). The cracks 24 partially follow the pores 22 in this layer 21.
- 25 is the corresponding crack in the glass ceramic of the mold. It is the case is drawn where tensile and bending stresses occur in layers 21 and 23.
- FIG. 14 shows a schematic elevation / section of a yielding mold consisting of a ductile ceramic film with powder filling: state before shrinking.
- 1 is the powder filling for the production of the component.
- 26 is a thin ductile ceramic sheet used in the green or semi-dry or partially heat treated condition. It is placed in a preform and heat treated for solidification or otherwise subjected to a hardening process. The powder is filled through a filling opening 27. 28 is a closure (adhesive joint) in the ceramic film.
- 15 relates to a schematic elevation / section of a yielding mold consisting of a sintered ceramic film with a sintered body: state after shrinking by sintering together.
- 3 is the sintered body, 20 the shell made of the sintered ceramic film.
- the arrows indicate the direction of movement during the shrinking process of the component. Since the shell 29 also shrinks at the same time, only the differential forces come into effect at the interfaces between the shell 29 and the sintered body 3. These can be positive or negative, depending on whether the shrinkage of the component or that of the shape predominates. In the first case, compressive forces arise in the mold (shell 29), in the second case tensile forces. It is advantageous to coordinate the shrinkage mass with one another by choosing the materials involved in each of FIGS. 3 and 29. A special case occurs when both shrinkage masses are the same. Then no forces are transferred.
- the yielding (i.e., elastic-plastically compliant or tearing) forms are produced according to the well-known conventional process of foundry and plastic molding technology and related technologies. Accordingly, the mold is usually produced using a model, the dimensions of which take account of the subsequent shrinkage during the sintering of the powder to produce the component.
- the method of melting wax, low-temperature metals and alloys, washing out salt or urea, burning out synthetic foam, etc. is practiced.
- the ceramic material required for the mold is applied to the model using the immersion, paste, casting and spraying process.
- Multi-part molds are usually made using models, dies, preforms, etc.
- Indestructible, elastic-plastic yielding forms are usually designed as thin-walled, highly porous shells, usually made up of several layers.
- Destructible shapes either have predetermined, predetermined breaking points or consist of thin shells that form net-like polygonal cracks under the forces that occur or disintegrate into mosaic-like fragments. These forces can also be triggered by process control (temperature, chemical reactions, structural changes).
- a powder with a maximum particle size of 50 ⁇ m was used which was produced by gas jet atomization.
- the powder was filled dry, without any binder into a ceramic form which gave about 10% more linear expansion, and cold pre-compacted by vibration.
- the procedure for producing the following mold was as follows: First of all, two preforms (matrices) for a two-part ceramic mold were produced, which depicted the component to be manufactured as a hollow mold, linearly enlarged by the shrinkage 10%.
- the filled, cold pre-compressed steel powder was sintered under vacuum (residual pressure 10 ⁇ 7 bar).
- the vacuum furnace and workpiece were first heated to 1000 ° C at a rate of 20 ° C / min, then to 1200 ° C at a rate of 5 ° C / min.
- the steel powder had the opportunity to sinter to such an extent that the workpiece already had sufficient inherent strength without having undergone any significant shrinkage.
- the workpiece to be sintered was further heated to a sintering temperature of 1360 ° C. and sintered for 6 hours.
- the yielding ceramic shape which consisted of sintered casting compound, reached such a level that it offered practically no resistance to the shrinkage of the steel component to be manufactured, but essentially retained its desired shape. Then the whole thing was cooled in the oven to approx. 250 ° C, whereby the shell-like ceramic shape cracked due to different thermal expansion coefficients and some shell parts were already flaking off. After removal from the oven, the component with the still adhering shell parts of the mold was quenched in cold water, the latter flaking off completely. The component was cleaned by blasting with glass beads, which resulted in a clean, smooth surface.
- Example I As a component, a blade corresponding to Example I was made of the Cr steel X20CrMoV 12 1 with the same dimensions.
- the divided metallic preforms (matrices) as used in Example I were used as tools.
- the residual moisture (H2O content) was approximately 2.5 to 3% by weight. 0.5% by volume of a silicate-based binder with the trade name "Silester X15" from Monsanto, Brussels, Belgium, was added to the mass with particles of up to 630 ⁇ m. It was filled into the die with vibration and pressing with a stamp. The green compact produced in this way had sufficient inherent strength to be handled for drying.
- the binder portion was cured on the way of a chemical reaction by treatment in an atmosphere containing NH 3 (ammonia curing) for 5 min. The ceramic mold was then air-dried for 30 minutes. The drying time depends on the dimensions the form approx. 10 to 60 min. This time was used to fill the resilient ceramic mold made of shells with the powder made of Cr steel.
- the ceramic mold was not necessary to fire the ceramic mold separately.
- the filled mold was moved into a vacuum oven, heated and sintered simultaneously with the powder of the component to be manufactured. Due to the low proportion of binder in the mold, the pollution of the furnace atmosphere is negligible. During this heat treatment, there was considerable shrinkage in the mold, so that the latter guaranteed sufficient support of the steel particles of the workpiece at all times, without, however, preventing them from shrinking themselves.
- the time / temperature program was carried out in such a way that the shrinkage of the workpiece and the shape took place at approximately the same speed and the same degree. In the present case, the whole was first heated to 1100 ° C. at a speed of approx.
- the powder used was generated by gas jet atomization and had a maximum particle size of 30 ⁇ m.
- 3 mm thick shells were produced from the borosilicate glass using dies as tools, cemented together and the shape formed in this way was subjected to heat treatment.
- the borosilicate separated into an almost pure, insoluble Si02 phase and a local sodium borate phase. The latter was dissolved out with 3N sulfuric acid, so that a microporous Si02 skeleton which retained the shape remained.
- the Cr / Ni steel powder was filled into this mold and the whole was heated to 1000 ° C.
- the steel powder sintered successively from 900 ° C in such a way that it already assumed sufficient inherent strength.
- the spongy structure of the mold shrank linearly by 15 to 20%.
- the complete sintering aimed at a component that was as dense as possible was dispensed with and the entire heat treatment was stopped prematurely (presintering).
- the whole, the component and the shape as a glass-encased workpiece was cooled and compressed into the finished part in a corresponding system by hot isostatic pressing.
- Glass and time / temperature program had previously been coordinated in such a way that there was no fear of recrystallization or breakage due to stresses occurring at the Si02 conversion.
- a blade corresponding to Example II was made of AISI 316 Cr / Ni steel. The dimensions were exactly the same as in Example III. The same matrices were also used.
- a paste-like mass of a foaming ceramic material based on sodium metasilicate was applied by spraying / spraying onto the positive molding of the respective die, dried, hardened and detached from the die.
- the two thin shells produced in this way had a wall thickness of 0.5 mm. They were glued together to give the ceramic form and filled with Cr / Ni steel powder. Then the whole, consisting of mold and powder filling, was placed in a box with a sand bed, surrounded on all sides with sand and heated to a temperature of 600 ° C. In the course of heating, the ceramic mass of the mold began to foam, creating a highly porous foam-like structure which displaced a corresponding volume of sand in the sand bed.
- the non-foamed skin-like inner wall of the shape thus formed was supported against the inside on the steel powder.
- the brittle foam ceramic was compressed (pressed in) in the zones near the surface by the shrinking process, although the partially broken framework of the component did not offer any appreciable resistance.
- a component with a comparatively smooth surface could be achieved.
- An approximate final shape of the component having multi-part metallic matrix was coated on the outside by flame spraying with an approximately 0.8 mm thick Al2O3 layer as an outer shell.
- Prismatic rectangular cores for the channels with grooves for the ribs were then produced.
- the material mullite (3Al2O3 ⁇ 2SiO2) was used in coarse-grained powder form with a particle diameter of 200 to 500 ⁇ m, to which a few percent by weight quartz (SiO2) was added as a binder.
- the yielding ceramic form composed of several Al2O3 shell parts and mullite cores was then filled with vibration with SiC powder with a particle size of 30 to 80 ⁇ m and the whole was subjected to a time-programmed heat treatment.
- the mixture was heated to a temperature of 300 ° C. at a rate of 100 ° C./h and held at this value for about 1/2 hour.
- the further heating to 1000 ° C was carried out at 200 ° C / h and that to 1100 ° C at a reduced speed of 20 ° C / h to the expected conversions (phases, modifications of SiO2 etc.) and the resulting volume changes leave time for the substances involved.
- the mixture was then heated to 1500 ° C. at 200 ° C./h and this temperature was maintained for 2 hours.
- the mullite already began to soften somewhat, so that it did not hinder the shrinkage of the silicon carbide component to be produced during the sintering process that now began. This was now at a temperature of 1600 ° C for 8 hours carried out. The cores shrank with it and the outer shell of the form (Al2O3) remained. After the sintering process was completed, the quench was cooled relatively quickly, forcing the outer shell of the mold to come off while the cores crumbled. With this example it could be shown that even comparatively complex components made of ceramic materials can be economically manufactured using the present process.
- the invention is not restricted to the exemplary embodiments.
- the method for shaping any component from a metallic and / or ceramic material, starting from a powder or a powder mixture, the powder being poured loosely into a mold and then subjected to a sintering process is carried out by using a flexible ceramic body as the mold , which yields elastically and / or plastically under the stresses that occur as a result of expansion or shrinkage, causing tensile and / or compressive forces due to expansion or shrinkage, and / or tears at targeted predetermined breaking points, however, its strength and dimensional stability in the entire temperature range and above the entire process sequence is sufficiently high to ensure a high dimensional accuracy of the component to be manufactured as a sintered body.
- the shape used is one or more thin, resilient ceramic shells made of high porosity Al2O3, SiO2 or MgO or a body made of a special glass which, when the sintering temperature of the powder mixture intended for the component is reached, tears in a net-like manner without completely breaking or disintegrating.
- a ceramic body is preferably used as the mold, which has predetermined breaking points in the form of notches at the locations of the highest tensile stresses in the course of the sintering process, and furthermore a ceramic shell which tears when the component is sintered and disintegrates into arbitrary mosaic-like fragments.
- the form used is a thin, flexible, elastic-plastic ceramic film in the green or only partially heat-treated state, which only in the course of the heating and sintering process, together with the powder used to produce the component, achieve its final strength through chemical processes and finished sintering receives.
- a green ceramic mass is advantageously used as the mold, which assumes its final shape and strength only during the drying and sintering process at the same time as the component is being sintered, with the associated shrinkage process only the positive or negative due to the different shrinkage of the shape and component Differential forces must be absorbed.
- Particularly favorable conditions are present if a material is used for the ceramic mass whose shrinkage due to the heating and sintering of the shape and the component is greater than the shrinkage of the powder used for the component, such that the component is subjected to during pressure is exerted during the sintering process while the wall of the mold is under tension.
- the powder or the powder mixture is preferably precompressed in the yielding form by centrifugal centrifugation before the heating to the sintering temperature or during the first phase of the heating in the lower temperature range.
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Powder Metallurgy (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Moulds, Cores, Or Mandrels (AREA)
- Multi-Conductor Connections (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH81790 | 1990-03-14 | ||
| CH817/90 | 1990-03-14 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0451467A1 true EP0451467A1 (fr) | 1991-10-16 |
| EP0451467B1 EP0451467B1 (fr) | 1995-02-08 |
Family
ID=4195889
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP91102428A Expired - Lifetime EP0451467B1 (fr) | 1990-03-14 | 1991-02-20 | Méthode de frittage utilisant un moule déformable en céramique |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US5077002A (fr) |
| EP (1) | EP0451467B1 (fr) |
| JP (1) | JPH04224606A (fr) |
| AT (1) | ATE118182T1 (fr) |
| DE (1) | DE59104523D1 (fr) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0633440A1 (fr) * | 1993-07-02 | 1995-01-11 | Abb Research Ltd. | Procédé pour la préparation d'un support de frittage |
| EP0701875A1 (fr) * | 1994-09-15 | 1996-03-20 | Basf Aktiengesellschaft | Procédé de préparation d'articles métalliques par moulage par injection |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5468193A (en) * | 1990-10-25 | 1995-11-21 | Sumitomo Heavy Industries, Ltd. | Inscribed planetary gear device having powder injection molded external gear |
| US6537487B1 (en) | 2000-06-05 | 2003-03-25 | Michael L. Kuhns | Method of manufacturing form tools for forming threaded fasteners |
| US6676895B2 (en) | 2000-06-05 | 2004-01-13 | Michael L. Kuhns | Method of manufacturing an object, such as a form tool for forming threaded fasteners |
| US20050227772A1 (en) * | 2004-04-13 | 2005-10-13 | Edward Kletecka | Powdered metal multi-lobular tooling and method of fabrication |
| US8601907B2 (en) | 2004-09-24 | 2013-12-10 | Kai U.S.A., Ltd. | Knife blade manufacturing process |
| US20070274854A1 (en) * | 2006-05-23 | 2007-11-29 | General Electric Company | Method of making metallic composite foam components |
| US7845549B2 (en) * | 2006-05-31 | 2010-12-07 | General Electric Company | MIM braze preforms |
| US20070295785A1 (en) * | 2006-05-31 | 2007-12-27 | General Electric Company | Microwave brazing using mim preforms |
| GB2517939B (en) * | 2013-09-05 | 2016-08-10 | Rolls Royce Plc | A method and apparatus for separating a canister and component |
| EP4313910A1 (fr) * | 2021-03-26 | 2024-02-07 | Corning Incorporated | Fabrication de dispositifs fluidiques et dispositifs fluidiques produits |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1788101A (en) * | 1928-07-19 | 1931-01-06 | Major E Gates | Mold and method of manufacturing the same |
| US3939241A (en) * | 1974-10-04 | 1976-02-17 | Crucible Inc. | Method for powder metallurgy compacting |
| FR2310825A1 (fr) * | 1975-05-13 | 1976-12-10 | Nat Forge Cy | Dispositif isostatique pour la fabrication de longues tiges |
| FR2353355A1 (fr) * | 1976-06-01 | 1977-12-30 | Special Metals Corp | Procede et appareil pour former des pieces frittees en superalliages |
| US4164527A (en) * | 1974-11-01 | 1979-08-14 | Bakul Valentin N | Method of making superhard articles |
| FR2435310A1 (fr) * | 1978-09-06 | 1980-04-04 | Asea Ab | Procede et machine de remplissage d'une capsule avec de la poudre |
| US4199339A (en) * | 1977-08-18 | 1980-04-22 | Motoren-Und Turbinen-Union Munich Gmbh | Method for the manufacture of a molded member from a ceramic material |
| EP0053753A1 (fr) * | 1980-12-05 | 1982-06-16 | Fried. Krupp Gesellschaft mit beschränkter Haftung | Procédé de fabrication d'ébauches métalliques |
| USRE31355E (en) * | 1976-06-03 | 1983-08-23 | Kelsey-Hayes Company | Method for hot consolidating powder |
| EP0203789A1 (fr) * | 1985-05-28 | 1986-12-03 | Nippon Kokan Kabushiki Kaisha | Procédé pour le moulage de poudres |
| US4673549A (en) * | 1986-03-06 | 1987-06-16 | Gunes Ecer | Method for preparing fully dense, near-net-shaped objects by powder metallurgy |
| US4724123A (en) * | 1987-02-09 | 1988-02-09 | The Dow Chemical Company | Plastic foam container for the densification of powder material |
| DE3805193A1 (de) * | 1988-02-19 | 1989-08-31 | Nmi Naturwissenschaftl U Mediz | Verfahren zur herstellung von hochfesten keramik-fasern und -formkoerpern und ihre verwendung |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA855149A (en) * | 1968-02-28 | 1970-11-03 | J. Havel Charles | Hot isostatic pressing using a vitreous container |
| GB2088414B (en) * | 1980-11-24 | 1985-01-09 | Nippon Dia Cleviteco Ltd | Sintering stainless steel powder |
| KR890003502B1 (ko) * | 1985-02-08 | 1989-09-23 | 가부시기가이샤 히다찌세이사꾸쇼 | 슬립캐스팅 성형법 및 성형용 주형 |
| US4722825A (en) * | 1987-07-01 | 1988-02-02 | The United States Of America As Represented By The Secretary Of The Navy | Method of fabricating a metal/ceramic composite structure |
| US4943320A (en) * | 1988-12-15 | 1990-07-24 | The Regents Of The University Of California | Vapor phase redistribution in multi-component systems |
-
1991
- 1991-02-20 EP EP91102428A patent/EP0451467B1/fr not_active Expired - Lifetime
- 1991-02-20 AT AT91102428T patent/ATE118182T1/de active
- 1991-02-20 DE DE59104523T patent/DE59104523D1/de not_active Expired - Fee Related
- 1991-03-12 US US07/668,210 patent/US5077002A/en not_active Expired - Fee Related
- 1991-03-14 JP JP3049890A patent/JPH04224606A/ja not_active Withdrawn
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1788101A (en) * | 1928-07-19 | 1931-01-06 | Major E Gates | Mold and method of manufacturing the same |
| US3939241A (en) * | 1974-10-04 | 1976-02-17 | Crucible Inc. | Method for powder metallurgy compacting |
| US4164527A (en) * | 1974-11-01 | 1979-08-14 | Bakul Valentin N | Method of making superhard articles |
| FR2310825A1 (fr) * | 1975-05-13 | 1976-12-10 | Nat Forge Cy | Dispositif isostatique pour la fabrication de longues tiges |
| FR2353355A1 (fr) * | 1976-06-01 | 1977-12-30 | Special Metals Corp | Procede et appareil pour former des pieces frittees en superalliages |
| USRE31355E (en) * | 1976-06-03 | 1983-08-23 | Kelsey-Hayes Company | Method for hot consolidating powder |
| US4199339A (en) * | 1977-08-18 | 1980-04-22 | Motoren-Und Turbinen-Union Munich Gmbh | Method for the manufacture of a molded member from a ceramic material |
| FR2435310A1 (fr) * | 1978-09-06 | 1980-04-04 | Asea Ab | Procede et machine de remplissage d'une capsule avec de la poudre |
| EP0053753A1 (fr) * | 1980-12-05 | 1982-06-16 | Fried. Krupp Gesellschaft mit beschränkter Haftung | Procédé de fabrication d'ébauches métalliques |
| EP0203789A1 (fr) * | 1985-05-28 | 1986-12-03 | Nippon Kokan Kabushiki Kaisha | Procédé pour le moulage de poudres |
| US4673549A (en) * | 1986-03-06 | 1987-06-16 | Gunes Ecer | Method for preparing fully dense, near-net-shaped objects by powder metallurgy |
| US4724123A (en) * | 1987-02-09 | 1988-02-09 | The Dow Chemical Company | Plastic foam container for the densification of powder material |
| DE3805193A1 (de) * | 1988-02-19 | 1989-08-31 | Nmi Naturwissenschaftl U Mediz | Verfahren zur herstellung von hochfesten keramik-fasern und -formkoerpern und ihre verwendung |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0633440A1 (fr) * | 1993-07-02 | 1995-01-11 | Abb Research Ltd. | Procédé pour la préparation d'un support de frittage |
| EP0701875A1 (fr) * | 1994-09-15 | 1996-03-20 | Basf Aktiengesellschaft | Procédé de préparation d'articles métalliques par moulage par injection |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04224606A (ja) | 1992-08-13 |
| US5077002A (en) | 1991-12-31 |
| EP0451467B1 (fr) | 1995-02-08 |
| DE59104523D1 (de) | 1995-03-23 |
| ATE118182T1 (de) | 1995-02-15 |
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