SiC particle reinforced oxynitride glass and glass-ceramic composites: crystallization and viscoplastic forming ranges

Journal Article · Sat Jun 01 04:00:00 EDT 1996 · Acta Materialia

DOI:https://doi.org/10.1016/1359-6454(95)00367-3· OSTI ID:271766

Rouxel, T ^[1]; Verdier, P ^[2]

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1. ENSCI, Limoges (France). Lab. de Materiaux Ceramiques et Traitements de Surface
2. Univ. de Rennes 1 (France). Lab. de Chimie des Materiaux

The viscoplastic forming and the crystallization ranges of SiC particle reinforced oxynitride glass composites were characterized. Crystallization starts beyond 1,050 C, with MgAl{sub 2}O{sub 4}, MgSiO{sub 3}, z- and {delta}-Y{sub 2}Si{sub 2}O{sub 7} as the main phases. A non-Newtonian flow behavior was observed from 800 to 900 C, i.e., on both sides of Tg (Tg = 863 C), with n {approx} 0.6 (shear thickening). The viscosity versus temperature curves (drawn from creep tests), show that temperature must be higher than 950 C for the viscosity to be lower than 10{sup 10} Pa s. In the light of these results, the feasibility for viscoplastic forming of a 40 vol.% SiC composite was demonstrated by shaping a parabolic shell at 980 C within 30 min.

• OSTI ID: 271766
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 6 Vol. 44; ISSN XZ504Y; ISSN 1359-6454
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM COMPOUNDS
CHEMICAL COMPOSITION
COMPOSITE MATERIALS
CRYSTALLIZATION
HOT PRESSING
KINETICS
MAGNESIUM COMPOUNDS
NITRIDES
OXIDES
POWDERS
SILICON CARBIDES
SILICON COMPOUNDS
TEMPERATURE DEPENDENCE
TRANSITION TEMPERATURE
VISCOSITY
X-RAY DIFFRACTION
YOUNG MODULUS
YTTRIUM COMPOUNDS