Sintering of fused silica to produce shaped bodies comprising crystalline SiO2

US8863552B2 · kind B2 · utility

Assignee

• Schott AG · DE

Inventors

• Manfred Borens · Mainz, DE
• Karsten von Westernhagen · Mainz, DE
• Stefano Merolla · Mainz, DE
• Gerald Wasem · Obermoschel, DE
• Stefan Postrach · Mainz, DE

Key dates

• Filing date: Jan 15, 2008
• Grant date: Oct 21, 2014
• Expiry date: Aug 13, 2030

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/1317
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A process is disclosed for simple and rapid production of a shaped body comprising fused silica and a shaped body which leads to virtually no contamination of a melt in contact with the shaped body even at high temperatures. The disclosed process comprises the steps of: a) provision of fused silica in the form of essentially amorphous SiO2 grains of which not more than 5% have a diameter greater than 15 mm, b) addition of water to the fused silica grains to produce a slip, c) casting of the slip into a mold which comprises a hollow body having the inverse shape of the shaped body to be produced, and d) drying of the slip to give an intermediate body, which is then sintered and cooled. A shaped body producible in accordance with the aforementioned process is also disclosed, which comprises at least 99.0 mol % of SiO2.