EP0733419A1 - Investment casting material - Google Patents
Investment casting material Download PDFInfo
- Publication number
- EP0733419A1 EP0733419A1 EP96104402A EP96104402A EP0733419A1 EP 0733419 A1 EP0733419 A1 EP 0733419A1 EP 96104402 A EP96104402 A EP 96104402A EP 96104402 A EP96104402 A EP 96104402A EP 0733419 A1 EP0733419 A1 EP 0733419A1
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- EP
- European Patent Office
- Prior art keywords
- casting
- oxide
- binder
- titanium
- maximum
- 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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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
Definitions
- the invention relates to a casting investment material on a ceramic basis for the production of casting molds by the lost wax process for casting titanium, titanium alloys or other metals which react violently with oxygen in the liquid state, which essentially have a basic composition with zirconium oxide and with other thermodynamically stable raw materials and additionally cement and Contains binders.
- a casting investment is described in EP-A-92104283.4.
- the known casting investment material is said to be particularly suitable for the production of casting molds for casting titanium. Due to its good mechanical properties and its biocompatibility, titanium is an almost ideal material for dental restorations. However, the great reactivity of the molten as well as the solid and still glowing titanium has so far been a major problem in casting technology.
- the investment material plays a key role in titanium casting.
- the investment material according to EP-A-92 104283.4 is said to contain quartz (SiO 2 ) and its modifications as a thermodynamically stable, ceramic raw material, mixed with 40-60% zirconium oxide or else aluminum oxide or magnesium oxide. A zirconium oxide content of less than 40% is expressly described as disadvantageous. Monoammonium phosphate (NH 4 H 2 PO 4 ) and magnesium oxide (MgO) are mentioned as binders.
- the investment material according to this document contains at least 40% components that react violently with titanium. To suppress this, the investment mixture should be hardened are stored and shaken in such a way that heavy zirconium oxide diffuses into the vicinity of the casting surface due to gravity.
- the invention is based on the problem of developing a casting investment of the type mentioned at the outset which has all the usual properties of the known phosphate-bound casting investments, but in which reactions between the metal and the material of the casting mold are prevented as far as possible.
- This problem is solved according to the invention in that a maximum of 35% magnesium oxide and a maximum of 50% zirconium oxide or calcium zirconate are provided as thermodynamically stable raw materials, 5-15% hydraulic calcium oxide cement and a maximum of 2% of an alkaline zirconate binder as a binder.
- This problem-solving is based on the knowledge that there are special alkaline zirconate binders outside the ceramic industry, so that hydraulic cements can be used to harden the casting investment material, which are known to harden only in alkaline media.
- the material In the cast investment material according to the invention there are no substances which react with the aggressive titanium. Nevertheless, the material is as easy to process as the previously used silicate and phosphate-containing casting investment materials.
- the zirconate binder required to implement the invention should be alkaline to neutral so as not to adversely affect the hardening of the calcium oxide cement. Depending on the desired processing time, the concentration should be a maximum of 2%.
- the calcium oxide-containing, silicate-free cement ensures the hardening of the cast slip into a hard mold.
- Fast-curing cements with a high CaO content (at least 45%) and the lowest possible Al 2 O 3 content are advantageous.
- the cement content is 5 - 15%.
- the magnesium oxide gives the finished powder mixture a homogeneous structure, improves the flowability of the slip and compensates for the difference between "heavy" zirconium oxide and other "lighter” components of the powder mixture. For this reason, the industrial bulk magnesium oxide powder should be preferred, with a purity of at least 98% being desirable. An optimal effect is achieved from about 20% to 35% MgO. A higher content leads, among other things because of the selected purity, to poorer casting results and a less than optimal behavior of the investment.
- zirconium oxide preference should be given to a fully stabilized electro-melt product with a small surface area, because such powders can be mixed into slurry with a small amount of liquid.
- the grain size should be chosen so that at least 50% of the powder is between 120 to 250 microns.
- the solidification contraction of the cast metal is usually compensated with a corresponding previous volume expansion of the casting mold.
- the contraction of the casting mold must also be compensated for, which occurs from the water outlet at 100 ° C and the sintering shrinkage from approx. 600 ° C.
- Investments of this type can be used with good results for cast titanium, but they are also advantageous at very high temperatures, for example for processing (glass) ceramic materials.
- the spinel formation is only completed at about 1600 ° C, so that the sintering shrinkage of the mold can be constantly compensated for with the increase in volume generated.
- additives can also be added to the investment powder or liquid, e.g. Liquefying agents, agents for achieving a higher gas permeability of the casting mold, dispersing agents, accelerators or retarders of cement hardening etc.
- Liquefying agents agents for achieving a higher gas permeability of the casting mold
- dispersing agents accelerators or retarders of cement hardening etc.
- the preference is always to give burnable or non-phosphate and silicate-containing substances.
- the investment material which is available as a powder and water-containing liquid, is processed similarly to the usual phosphate-bonded investment materials. After mixing the two components, a plastic, flowable slip is created. The wax-up is then cast in. The processing time can be set up to 15 'so that there is enough time for corrections.
- the cement hardening gradually stiffens the casting mold until, after approx. 1/2 - 2 hours - depending on the composition - a sufficiently hard casting mold is obtained. In the event of a fire, a holding level at 150-300 ° C is preferred to allow the water to slowly escape from the ceramic mold.
- the further rise in temperature can basically take place relatively quickly - thanks to the low thermal expansion of the raw materials. However, the overall temperature profile also depends on the expansion medium used.
- the casting mold is preferably subsequently cooled to approximately 450 ° C., annealed and cast with titanium in a casting plant.
- the investment described does not adhere to the casting when devesting and can be removed by hand.
- the cast surface is metallic clean to shiny, with a strongly reduced alpha-case zone, which is only for impurities of raw materials and alumina.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Mold Materials And Core Materials (AREA)
- Dental Prosthetics (AREA)
- Dental Preparations (AREA)
Abstract
Description
Die Erfindung betrifft eine Gußeinbettmasse auf keramischer Basis für die Herstellung von Gußformen nach dem Wachsausschmelzverfahren zum Gießen von Titan, Titanlegierungen oder anderen im flüssigen Zustand heftig mit Sauerstoff reagierenden Metallen, welche im wesentlichen eine Grundmasse mit Zirkonoxid und mit anderen thermodynamisch stabilen Rohstoffen und zusätzlich Zement und Bindemittel enthält. Eine solche Gußeinbettmasse ist in der EP-A-92104283.4 beschrieben.The invention relates to a casting investment material on a ceramic basis for the production of casting molds by the lost wax process for casting titanium, titanium alloys or other metals which react violently with oxygen in the liquid state, which essentially have a basic composition with zirconium oxide and with other thermodynamically stable raw materials and additionally cement and Contains binders. Such a casting investment is described in EP-A-92104283.4.
Die bekannte Gußeinbettmasse soll sich insbesondere für die Erstellung von Gußformen zum Gießen von Titan eignen. Titan ist aufgrund von guten mechanischen Eigenschaften und seiner Biokompatibilität ein nahezu idealer Werkstoff für dentale Restaurationen. Die große Reaktionsfreudigkeit des geschmolzenen sowie auch festen und noch glühenden Titans stellt bei der Gußtechnik bisher jedoch ein großes Problem dar.The known casting investment material is said to be particularly suitable for the production of casting molds for casting titanium. Due to its good mechanical properties and its biocompatibility, titanium is an almost ideal material for dental restorations. However, the great reactivity of the molten as well as the solid and still glowing titanium has so far been a major problem in casting technology.
Der Einbettmasse kommt gerade beim Titanguß eine Schlüsselrolle zu. Die Einbettmasse nach der genannten EP-A-92 104283.4 soll als thermodynamisch stabilen, keramischen Rohstoff Quarz (SiO2) und seine Modifikationen, gemischt mit 40 - 60 % Zirkonoxid oder aber auch Aluminiumoxid oder Magnesiumoxid enthalten. Ein Zirkonoxidgehalt von weniger als 40 % wird ausdrücklich als nachteilig bezeichnet. Als Bindemittel werden Monoammonium-Phosphat (NH4H2PO4) und Magnesiumoxid (MgO) genannt. Die Einbettmasse nach dieser Schrift enthält also mindestens 40 % Bestandteile, die mit Titan heftig reagieren. Um dies zu unterdrücken, soll die Einbettmassenmischung vor dem Aushärten so gelagert und geschüttelt werden, daß schweres Zirkonoxid schwerkraftbedingt in die Nähe der Gußoberfläche diffundiert. Es hat sich jedoch gezeigt, daß auch dies nicht zu sauberen und glänzenden Oberflächen der Gußstücke führt, weil aggressive Metalle, insbesondere Titan, sehr heftig mit Siliziumdioxiden und Phosphaten reagieren. Das führt zu einem sehr festen Haften des Gußstückes an der die Gußform bildenden Einbettmasse, zu einer dicken Oxidschicht an der Gußteiloberfläche und zur Diffusion von Sauerstoff in die Oberfläche des Gußteils und damit zur Ausbildung einer sehr spröden und rißanfälligen Zone, der sogenannten "alpha-case" (bis 0,3 mm dick), die nachträglich entfernt werden muß.The investment material plays a key role in titanium casting. The investment material according to EP-A-92 104283.4 is said to contain quartz (SiO 2 ) and its modifications as a thermodynamically stable, ceramic raw material, mixed with 40-60% zirconium oxide or else aluminum oxide or magnesium oxide. A zirconium oxide content of less than 40% is expressly described as disadvantageous. Monoammonium phosphate (NH 4 H 2 PO 4 ) and magnesium oxide (MgO) are mentioned as binders. The investment material according to this document contains at least 40% components that react violently with titanium. To suppress this, the investment mixture should be hardened are stored and shaken in such a way that heavy zirconium oxide diffuses into the vicinity of the casting surface due to gravity. However, it has been shown that this does not lead to clean and shiny surfaces of the castings, because aggressive metals, especially titanium, react very violently with silicon dioxide and phosphates. This leads to a very firm adhesion of the casting to the investment material forming the casting mold, to a thick oxide layer on the casting surface and to the diffusion of oxygen into the surface of the casting and thus to the formation of a very brittle and crack-prone zone, the so-called "alpha-case""(up to 0.3 mm thick), which must be removed afterwards.
Der Erfindung liegt das Problem zugrunde, eine Gußeinbettmasse der eingangs genannten Art zu entwickeln, welche alle üblichen Eigenschaften der bekannten phosphatgebundenen Gußeinbettmassen besitzt, bei der jedoch Reaktionen zwischen dem Metall und dem Material der Gußform möglichst weitgehend verhindert werden.The invention is based on the problem of developing a casting investment of the type mentioned at the outset which has all the usual properties of the known phosphate-bound casting investments, but in which reactions between the metal and the material of the casting mold are prevented as far as possible.
Dieses Problem wird erfindungsgemäß dadurch gelöst, daß als thermodynamisch stabile Rohstoffe maximal 35 % Magnesiumoxid und maximal 50 % Zirkonoxid oder Calciumzirkonat, als Zement 5 - 15 % hydraulischer Calciumoxidzement und als Bindemittel maximal 2 % eines alkalischen Zirkonatbinders vorgesehen sind.This problem is solved according to the invention in that a maximum of 35% magnesium oxide and a maximum of 50% zirconium oxide or calcium zirconate are provided as thermodynamically stable raw materials, 5-15% hydraulic calcium oxide cement and a maximum of 2% of an alkaline zirconate binder as a binder.
Dieser Problemlösung liegt die Erkenntnis zugrunde, daß es außerhalb der keramischen Industrie spezielle alkalische Zirkonatbinder gibt, so daß man zum Aushärten der Gußeinbettmasse hydraulische Zemente anwenden kann, die bekanntlich nur in alkalischen Medien härten.This problem-solving is based on the knowledge that there are special alkaline zirconate binders outside the ceramic industry, so that hydraulic cements can be used to harden the casting investment material, which are known to harden only in alkaline media.
In der erfindungsgemäßen Gußeinbettmasse sind keine Stoffe vorhanden, welche mit dem aggressiven Titan reagieren. Dennoch ist das Material vergleichbar gut zu verarbeiten wie die bisher gebräuchlichen silikat- und phosphathaltigen Gußeinbettmassen. Der für die Verwirklichung der Erfindung erforderliche Zirkonatbinder sollte alkalisch bis neutral sein, um die Härtung des Calciumoxidzements nicht negativ zu beeinflussen. Die Konzentration sollte, abhängig von der gewünschten Verarbeitungszeit, bei maximal 2 % liegen.In the cast investment material according to the invention there are no substances which react with the aggressive titanium. Nevertheless, the material is as easy to process as the previously used silicate and phosphate-containing casting investment materials. The zirconate binder required to implement the invention should be alkaline to neutral so as not to adversely affect the hardening of the calcium oxide cement. Depending on the desired processing time, the concentration should be a maximum of 2%.
Der calciumoxidhaltige, silikatfreie Zement gewährleistet die Härtung des gegossenen Schlickers zu einer harten Gußform. Von Vorteil sind hierbei schnell härtende Zemente mit einem hohen CaO-Gehalt (mindestens 45 %) und einem möglichst niedrigen Al2O3-Gehalt. Je nach gewünschter Härtezeit (Abbindezeit) liegt der Zement-Gehalt bei 5 - 15 %.The calcium oxide-containing, silicate-free cement ensures the hardening of the cast slip into a hard mold. Fast-curing cements with a high CaO content (at least 45%) and the lowest possible Al 2 O 3 content are advantageous. Depending on the desired hardening time (setting time), the cement content is 5 - 15%.
Das Magnesiumoxid verhilft dem fertigen Pulvergemisch zu einem homogenen Gefüge, verbessert die Fließfähigkeit des Schlickers und gleicht den Unterschied zwischen "schwerem" Zirkonoxid und anderen "leichteren" Bestandteilen des Pulvergemisches aus. Aus diesem Grund sollte das industrielle Magnesiumoxidpulver mit einem hohen Schüttgewicht bevorzugt werden, wobei eine Reinheit von mindestens 98 % wünschenswert ist. Eine optimale Wirkung wird ab ca 20 % bis 35 % MgO erreicht. Ein höherer Gehalt führt, neben anderem wegen der gewählten Reinheit, zu schlechteren Gußergebnissen und einem nicht optimalen Verhalten der Einbettmasse.The magnesium oxide gives the finished powder mixture a homogeneous structure, improves the flowability of the slip and compensates for the difference between "heavy" zirconium oxide and other "lighter" components of the powder mixture. For this reason, the industrial bulk magnesium oxide powder should be preferred, with a purity of at least 98% being desirable. An optimal effect is achieved from about 20% to 35% MgO. A higher content leads, among other things because of the selected purity, to poorer casting results and a less than optimal behavior of the investment.
Bei dem Zirkonoxid ist der Vorzug einem vollstabilisierten Elektroschmelzprodukt mit geringer Oberfläche zu geben, weil solche Pulver mit geringer Menge an Flüssigkeit zu Schlicker anmischbar sind. Die Korngröße soll dabei so gewählt werden, daß mindestens 50 % des Pulvers zwischen 120 bis 250 Mikron liegt.In the case of zirconium oxide, preference should be given to a fully stabilized electro-melt product with a small surface area, because such powders can be mixed into slurry with a small amount of liquid. The grain size should be chosen so that at least 50% of the powder is between 120 to 250 microns.
Optimale Wirkung erreicht man mit 20 bis 35 % Zirkonoxid. Eine höhere Menge führt zu einem schlechteren Zusammenhalt der Gußeinbettmasse. Bei über 50 % Zirkonoxid ergibt sich keine homogene Einbettmasse mehr.Optimal effect is achieved with 20 to 35% zirconium oxide. A higher amount leads to poorer cohesion of the casting investment. With over 50% zirconium oxide there is no longer a homogeneous investment.
Für die genaue Passung der dentalen Gußstücke wird üblicherweise die Erstarrungskontraktion des gegossenen Metalls mit einer entsprechenden vorherigen Volumenexpansion der Gußform kompensiert. Zusätzlich muß auch die Kontraktion der Gußform ausgeglichen werden, die durch den Wasseraustritt ab 100° C und die Sinterschrumpfung ab ca. 600° C eintritt. Neben der thermischen Dehnung der Rohstoffe, die aber bei den oben genannten relativ gering ist, wird das Problem folgendermaßen gelöst:For the exact fit of the dental castings, the solidification contraction of the cast metal is usually compensated with a corresponding previous volume expansion of the casting mold. In addition, the contraction of the casting mold must also be compensated for, which occurs from the water outlet at 100 ° C and the sintering shrinkage from approx. 600 ° C. In addition to the thermal expansion of the raw materials, which is relatively low for the above, the problem is solved as follows:
Es ist bekannt, daß bei einer Reihe von Festkörperreaktionen, bei denen Spinelle gebildet werden, eine unterschiedlich große Volumenzunahme eintritt. Aufgrund der Tatsache, daß in der Einbettmasse Magnesiumoxid vorliegt, führt der Zusatz von Aluminiumoxid zur Bildung von MgAl2O4-Spinell bei Temperaturen von 950 - 1300° C und einer entsprechenden Volumenzunahme. Vorzugsweise wird hochreaktives Aluminiumoxid Al2O3 zu 15 - 25 % dem Pulvergemisch zugesetzt. Zum verbesserten Ablauf der Festkörperreaktion schon bei niedrigeren Temperaturen bzw. mit niedrigerem Al2O3-Gehalt kann dem Einbettmassenpulver eine Reihe von Keimbildnern zugesetzt werden (MgAl2O4, FexOy, B2O3, CrO3 ...).It is known that in a number of solid-state reactions in which spinels are formed, the volume increases differently. Due to the fact that magnesium oxide is present in the investment material, the addition of aluminum oxide leads to the formation of MgAl 2 O 4 spinel at temperatures of 950-1300 ° C. and a corresponding increase in volume. Highly reactive aluminum oxide Al 2 O 3 is preferably added to the powder mixture in an amount of 15-25%. A number of nucleating agents (MgAl 2 O 4 , Fe x O y , B 2 O 3 , CrO 3 ...) can be added to the investment powder to improve the solid-state reaction even at lower temperatures or with a lower Al 2 O 3 content. .
Einbettmassen dieser Art kann man mit gutem Ergebnis für Titanguß einsetzen, vorteilhaft ist sie aber auch bei sehr hohen Temperaturen, z.B. für Bearbeitung von (glas)keramischen Materialien. Die Spinellbildung wird erst bei ca. 1600° C vollständig abgeschlossen, so daß die Sinterschrumpfung der Gußform ständig mit der erzeugten Volumenzunahme kompensiert werden kann.Investments of this type can be used with good results for cast titanium, but they are also advantageous at very high temperatures, for example for processing (glass) ceramic materials. The spinel formation is only completed at about 1600 ° C, so that the sintering shrinkage of the mold can be constantly compensated for with the increase in volume generated.
Dem Einbettmassenpulver bzw. der Flüssigkeit können zusätzlich geringe Mengen an Additiven zugemischt werden, z.B. Verflüssigungsmittel, Mittel zum Erreichen einer höheren Gasdurchlässigkeit der Gußform, Dispergiermittel, Beschleuniger bzw. Verzögerer der Zementhärtung usw. Der Vorzug ist dabei immer ausbrennbaren bzw. nicht phosphat- und silikathaltigen Stoffen zu geben.Small amounts of additives can also be added to the investment powder or liquid, e.g. Liquefying agents, agents for achieving a higher gas permeability of the casting mold, dispersing agents, accelerators or retarders of cement hardening etc. The preference is always to give burnable or non-phosphate and silicate-containing substances.
Die Einbettmasse, die als Pulver und wasserhaltige Flüssigkeit vorliegt, wird ähnlich den üblichen phosphatgebundenen Einbettmassen verarbeitet. Nach Anmischen der beiden Komponenten entsteht ein plastischer, fließfähiger Schlicker. Die Wachsmodellation wird damit eingegossen. Die Verarbeitungszeit kann auf bis zu 15' eingestellt werden, so daß genug Zeit für Korrekturen bleibt. Die Zementhärtung bewirkt eine allmähliche Versteifung der Gußform, bis nach ca. 1/2 - 2 Std. - je nach Zusammensetzung - eine ausreichend harte Gußform vorliegt. Beim Brand wird vorzugsweise eine Haltestufe bei 150 - 300° C gewählt, um das Wasser aus der keramischen Form langsam entweichen zu lassen. Der weitere Temperaturanstieg kann grundsätzlich - dank der geringen thermischen Dehnung der Rohstoffe - relativ schnell erfolgen. Das gesamte Temperaturprofil hängt jedoch auch von dem benutzen Expansionsmittel ab. Beim dentalen Titanguß wird die Gußform nachher vorzugsweise auf ca. 450° C abgekühlt, getempert und in einer Gußanlage mit Titan gegossen.The investment material, which is available as a powder and water-containing liquid, is processed similarly to the usual phosphate-bonded investment materials. After mixing the two components, a plastic, flowable slip is created. The wax-up is then cast in. The processing time can be set up to 15 'so that there is enough time for corrections. The cement hardening gradually stiffens the casting mold until, after approx. 1/2 - 2 hours - depending on the composition - a sufficiently hard casting mold is obtained. In the event of a fire, a holding level at 150-300 ° C is preferred to allow the water to slowly escape from the ceramic mold. The further rise in temperature can basically take place relatively quickly - thanks to the low thermal expansion of the raw materials. However, the overall temperature profile also depends on the expansion medium used. In the case of dental titanium casting, the casting mold is preferably subsequently cooled to approximately 450 ° C., annealed and cast with titanium in a casting plant.
Die beschriebene Einbettmasse haftet beim Ausbetten nicht am Gußstück und läßt sich von Hand entfernen. Die Gußoberfläche ist metallisch sauber bis glänzend, mit einer stark reduzierten alpha-case Zone, die nur auf Verunreinigungen der Rohstoffe und Aluminiumoxid zurückzuführen ist.The investment described does not adhere to the casting when devesting and can be removed by hand. The cast surface is metallic clean to shiny, with a strongly reduced alpha-case zone, which is only for impurities of raw materials and alumina.
Claims (3)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE1995110151 DE19510151A1 (en) | 1995-03-21 | 1995-03-21 | Cast investment |
| DE19510151 | 1995-03-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP0733419A1 true EP0733419A1 (en) | 1996-09-25 |
Family
ID=7757227
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP96104402A Withdrawn EP0733419A1 (en) | 1995-03-21 | 1996-03-20 | Investment casting material |
Country Status (2)
| Country | Link |
|---|---|
| EP (1) | EP0733419A1 (en) |
| DE (1) | DE19510151A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19649306A1 (en) * | 1996-11-28 | 1998-06-04 | Stanislav Dr Chladek | Ceramic embedding composition |
| DE19929290A1 (en) * | 1999-06-25 | 2000-12-28 | Volkswagen Ag | Process for the production of magnesium-containing metal castings |
| WO2003047790A1 (en) * | 2001-12-07 | 2003-06-12 | Schütz-Dental GmbH | Casting material for producing casting molds for casting high-melting point materials |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19846604A1 (en) * | 1998-10-09 | 2000-04-13 | Schuetz Dental Gmbh | Investment, for lost wax casting of high melting reactive material especially titanium, contains oxygen-reactive metal, metal carbide and-or metal nitride powder as expansion additive |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59166341A (en) * | 1983-11-11 | 1984-09-19 | Ohara:Kk | Casting mold for casting titanium |
| JPS61273233A (en) * | 1985-05-27 | 1986-12-03 | Kyocera Corp | Molding material for precision casting and casting method using same |
| DE3825250A1 (en) * | 1987-07-27 | 1989-02-09 | Morita Mfg | GIESSFORMSTOFF FOR USE IN A FEUNGIESSFORM AND MADE OF SUCH A CASTING MOLDED FEINGIESSFORM |
| EP0433546A1 (en) * | 1989-12-19 | 1991-06-26 | Iwatani Sangyo Kabushiki Kaisha( Iwatani International Corporation) | Nonsilica mold material for dental titanium cast |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4319925A (en) * | 1981-03-06 | 1982-03-16 | Weston Research Corporation | Coating compositions for metal casting molds |
| JPH0613137B2 (en) * | 1989-06-30 | 1994-02-23 | 岡崎鑛産物株式会社 | Mold material |
| DE4030542C1 (en) * | 1990-09-27 | 1992-03-19 | Shera-Werkstofftechnologie Gmbh, 2844 Lemfoerde, De | Ceramic for moulds for producing fine mouldings - comprises magnesia-silica-magnesium phosphate with silicon carbide and/or silicon nitride to prevent vol. decrease during heating |
| DE4107919C1 (en) * | 1991-03-12 | 1992-08-27 | Cowadental Cohen & Co. Gmbh, 4000 Duesseldorf, De |
-
1995
- 1995-03-21 DE DE1995110151 patent/DE19510151A1/en not_active Withdrawn
-
1996
- 1996-03-20 EP EP96104402A patent/EP0733419A1/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59166341A (en) * | 1983-11-11 | 1984-09-19 | Ohara:Kk | Casting mold for casting titanium |
| JPS61273233A (en) * | 1985-05-27 | 1986-12-03 | Kyocera Corp | Molding material for precision casting and casting method using same |
| DE3825250A1 (en) * | 1987-07-27 | 1989-02-09 | Morita Mfg | GIESSFORMSTOFF FOR USE IN A FEUNGIESSFORM AND MADE OF SUCH A CASTING MOLDED FEINGIESSFORM |
| EP0433546A1 (en) * | 1989-12-19 | 1991-06-26 | Iwatani Sangyo Kabushiki Kaisha( Iwatani International Corporation) | Nonsilica mold material for dental titanium cast |
Non-Patent Citations (2)
| Title |
|---|
| PATENT ABSTRACTS OF JAPAN vol. 009, no. 018 (M - 353) 25 January 1985 (1985-01-25) * |
| PATENT ABSTRACTS OF JAPAN vol. 011, no. 131 (M - 584) 24 April 1987 (1987-04-24) * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19649306A1 (en) * | 1996-11-28 | 1998-06-04 | Stanislav Dr Chladek | Ceramic embedding composition |
| DE19649306C2 (en) * | 1996-11-28 | 1999-02-11 | Stanislav Dr Chladek | Ceramic investment material for the production of molds |
| DE19929290A1 (en) * | 1999-06-25 | 2000-12-28 | Volkswagen Ag | Process for the production of magnesium-containing metal castings |
| WO2003047790A1 (en) * | 2001-12-07 | 2003-06-12 | Schütz-Dental GmbH | Casting material for producing casting molds for casting high-melting point materials |
Also Published As
| Publication number | Publication date |
|---|---|
| DE19510151A1 (en) | 1996-09-26 |
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