Method for curing cracks in ceramic shaped bodies and shaped bodies treated in such a manner

US6638568B1 · kind B1 · utility

Assignee

• Nexans Superconductors GmbH · DE

Inventors

• Michael Baecker · Cologne, DE
• Joachim Bock · Lechenich, DE
• Herbert Freyhardt · Oettingen, DE
• Andreas Leenders · Oettingen, DE
• Heribert Walter · Oebisfelde, DE
• Martin Ullrich · Leverkusen, DE

Key dates

• Filing date: Jul 31, 2001
• Grant date: Oct 28, 2003
• Expiry date: Jul 31, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10N60/0661
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A method of curing cracks in a ceramic shaped body made from ceramic magnet materials or ceramic superconductor materials, in which a filling material which melts at a lower temperature than the material of the shaped body or is flowable at a lower temperature than the material of the shaped body is applied to the surface of the shaped body at least in the area of a crack and/or is introduced into at least one crack, in which the shaped body with the filling material is heated to and maintained at a temperature at which the material of the shaped body does not yet melt or is not yet flowable, but at which the filling material is in at least partially molten and flowable state at least until the fused filling material can penetrate at least partially into the crack, in which the filling material consists of non-metallic or essentially of non-metallic compounds and is at least partially crystallized, and in which the shaped body with the filling material is cooled, wherein the thermal crystallization conditions for the filling material are selected in such a way that the filling material grows epitaxially on the crack face.