DE3531017A1

DE3531017A1 - Direct preparation of dental alloy castings from metal powder mixtures

Info

Publication number: DE3531017A1
Application number: DE19853531017
Authority: DE
Inventors: Nobert Prof Dipl Chem D Nowack; Harald Dr Med Schwander; Wolfgang Petroll
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-08-30
Filing date: 1985-08-30
Publication date: 1987-03-12

Abstract

Metal powder mixtures are prepared and then fused in dental engineering melting apparatus and cast to give high-grade dental prosthesis parts. The metal powder mixtures can contain metal carbides or/and carbon or/and silicon carbide. The metal powder mixtures can also contain exothermic powder constituents, so that the fusion process can proceed at a higher rate. To prevent high-temperature oxidation and for an accelerated fusion process, the metal powder mixtures can be prepressed and presintered to give compact parts. The pressing and sintering takes place under inert gas atmosphere. The sintering temperature and pressing force depend on the nature of the metal powder mixture (at least three components). This invention achieves several goals: preparation of highly pure alloy parts which are free of secondary constituents which otherwise impair the biocompatibility; and the current detour via the use of premolten master alloys to give castings is avoided (complications). The desirable range of variation of dental alloys is increased.

Description

State of the art in dental alloy technology and progress made by this invention

Zur Herstellung von Metallteilen in der zahnärztlichen Prothetik werden wegen der individuell verschiedenen Herstellung von Legierungsteilen nur kleine Legierungsteile in einem Arbeitsgang hergestellt. Größenordnungsmäßig liegen die Legierungsansätze, die geschmolzen und anschließend vergossen werden zwischen 10 bis 100 g. Dies sind verhältnismäßig geringe Mengen, die zu hochwertigen Gußteilen be nötigt werden.For the production of metal parts in dental prosthetics because of the individually different production of alloy parts only small alloy parts manufactured in one operation. The molten alloy approaches are on the order of magnitude and then shed between 10 to 100 g. these are comparatively small quantities, which are used for high-quality castings be compelled.

Derzeit werden in einem dentaltechnischen Betrieb bereits vorge schmolzene Legierungen eingesetzt. Diese Legierungen werden in einem komplexen Verfahren in Würfel-, Plättchen-, Zylinderform o. ä. industriell vorgeschmolzen (Größenordnung pro Teil ca. 10 g), um dann anschließend im Dentalbereich wieder aufgeschmolzen zu werden. Die Herstellung der Vorlegierung ist sehr arbeitsaufwendig und kostenintensiv. Durch das industrielle Angebot von Vorlegierungen wird eine wünschenswerte Variationsbreite der Dentallegierungs sorten sehr eingeengt.At present, dental technology operations are already being carried out molten alloys used. These alloys are made in a complex process in the form of cubes, platelets, cylinders or similar industrially premelted (order of magnitude approx. 10 g per part) in order to then to be melted again in the dental field. The preparation of the master alloy is very labor intensive and expensive. Through the industrial offer of master alloys becomes a desirable range of variation of the dental alloy varieties very restricted.

Durch diese Erfindung wird der Umweg über die Herstellung von Vorlegierungen vermieden, Kosten für hochwertige Prothetikteile gesenkt, die Variationsbreite bei der Anwendung von Legierungen im Dentalbereich wesentlich gesteigert.With this invention, the detour via the production of Pre-alloys avoided, costs for high-quality prosthetic parts reduced the range of variation when using alloys significantly increased in the dental field.

Die Herstellung von Dentallegierungen wird vereinfacht.The production of dental alloys is simplified.

Die Anforderungen an Dentallegierungen sind sehr vielfältiger Art:The requirements for dental alloys are very diverse:

Mechanische Eigenschaften, Oberflächengüten, Polierbarkeit, Be arbeitbarkeit, Vergießbarkeit, Paßgenauigkeit des Gusses, Bio kompatibilität und Korrosionseigenschaften, Haftbarkeit zu Porzellan, Lötbarkeit. Diese Eigenschaften sind primär von der chemischen Zu sammensetzung der Legierung abhängig. Durch diese Erfindung ist es möglich, daß eine gewünschte und auch individuelle Variation der Legierungseigenschaften stattfinden kann.Mechanical properties, surface qualities, polishability, loading workability, pourability, accuracy of fit of the cast, organic compatibility and corrosion properties, liability to porcelain, Solderability. These properties are primarily due to the chemical properties composition of the alloy. Through this invention it is possible that a desired and also individual variation of the Alloy properties can take place.

Claims

1) Production of dental alloy castings, characterized by the melting of metal powder mixtures in melting equipment in dental technology to form castable dental alloys.

2) Manufacture of dental alloy castings, marked in that the metal powder mixtures to a large extent ge presses and / or sintered (pellets) and when melting of these coarse metal powder parts in the melting apparatus the liquid alloy is formed.

3) This claim is characterized in that the metal powder mixture according to claim 1) and 2) metal particles under 3 mm grain size included.

4) This claim is characterized in that the metal powder Mixtures according to claim 1) and 2) also metal carbides or / and Carbon or / and silicon carbide in particle form (Grain size smaller than 3 mm) can contain.

5) This claim is characterized in that the metal powder according to claim 1), 2) and 4) with the addition of flux agents (mixtures of oxides, borates, phosphates, silicates, Carbonates and fluorides) that are below the liquidus temperature the alloy become liquid, be melted.

6) This claim is characterized in that the metal powder Mixtures according to claim 1), 2) and 4) with the participation of Thermite powder mixtures are melted.

7) This claim is characterized in that the metal powder Mixtures according to claim 1), 2) and 4) using of fluxes (as in claim 5)) and thermal mixtures (as in claim 6)) are melted.