Process for producing a non-dense sintered ceramic molded body having at least two layers

US10391671B2 · kind B2 · utility

Assignee

• Vita Zahnfabrik H. Rauter GmbH & Co. KG · DE

Inventors

• Michael Tholey · Bad Säckingen, DE
• Michael Dorn · Frick, CH
• Michael Gödiker · Clingen, DE
• Norbert Thiel · Annaberg-Buchholz, DE

Key dates

• Filing date: Apr 16, 2013
• Grant date: Aug 27, 2019
• Expiry date: May 20, 2033

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/24997
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process for producing a non-dense sintered ceramic molded body having at least two layers, wherein a first powdery ceramic material forming a layer is contacted with at least a second powdery material forming at least a second layer; said first powdery material has a presintering temperature T1 that is higher than the presintering temperature Ts of said at least second powdery ceramic material; the course of a curve of shrinkage S1 of said at least first powdery ceramic material differs from the course of a curve of shrinkage S2 of said at least second powdery material, wherein curve of shrinkage S1 is shifted towards higher temperatures as compared to curve of shrinkage S2; and the layers are subjected to a common temperature treatment at a presintering temperature Ts that is lower than the presintering temperature T1 and at least equal to T3 to cause sintering that remains in a stage of sintering that has not proceeded to the theoretical density; wherein the curve of shrinkage S1 is modified by admixing at least one component having a curve of shrinkage S3 which material is compatible with said powdery ceramic material into said first powdery ceramic material, i. e. has a grain…