Dense silicon nitride composite material

US5948717A · kind A · utility

Assignee

• FRAUNHOFER-GESELSCHAFT · DE

Inventors

• Hagen Klemm · Dresden, DE
• Mathias Herrmann · Sachsen, DE
• Katja Tangermann · Dresden, DE
• Christian Schubert · Domat/Ems, CH

Key dates

• Filing date: May 14, 1997
• Grant date: Sep 7, 1999
• Expiry date: May 14, 2017

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B35/5935
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The invention discloses a dense silicon nitride composite material which may be used as a high-temperature component in building armatures and motors with a long service life and high reliability even at higher temperatures. More specifically, the invention discloses a dense silicon nitride composite material containing 3 to 50 wt. % of a reinforcing component, in which the reinforcing component contains 10 to 90 wt. % Me.sub.5 Si.sub.3 and the remaining portion is either MeSi.sub.2 or MeSi.sub.2 and silicides with other stoichiometries and Me is a metal or a mixture of metals. The present invention is made by a method in which the material is produced by sintering and/or hot pressing and/or hot isostatic pressing and the reinforcing components are added as Me.sub.5 Si.sub.3 and MeSi.sub.2 powder or as a preliminary stage in which, until closed porosity is achieved, a nitrogen pressure/temperature ratio corresponding to a predetermined relationship is maintained which results in the formation and stabilization of Me.sub.5 Si.sub.3.