ChemInform Abstract: Amorphous Silicoboron Carbonitride Ceramic with Very High Viscosity at Temperatures above 1500 °C.

✍ Scribed by Ralf Riedel; Lutz M. Ruswisch; Linan An; Rishi Raj

• Book ID: 101874833
• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 34 KB
• Volume: 30
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199914284

✦ Synopsis

Amorphous Silicoboron Carbonitride Ceramic with Very High Viscosity at Temperatures above 1500 • C. -Recently, the viscosity of a predominantly amorphous Si carbide alloy, Si 1.7 C 1.0 N 1.5 , with an apparent glass transition temp. of 1400-1500 • C was studied. In this paper the creep behavior of the title ceramic of composition Si 2 B 1.0 C 3.4 N 2.3 , which appears to have a glass transition temp. of ¿1700 • C, is examined. Both materials show a three stage creep behavior. In stage I, the creep rate declines, in stage II, the strain rate approaches a steady state, and in stage III, it resumes a declining strain rate, which ultimately decreases below the measurement limit of the system. At 1500 • C in stage II, the viscosity of the silicoboron carbonitride is six orders of magnitude higher than that of fused silica.