Affiliation:
1. Instituto Militar de Engenharia
2. Centro Universitário de Volta Redonda
3. Arsenal de Guerra General Câmara
4. UERJ/Centro Brasileiro de Pesquisas Físicas
Abstract
The mechanical properties and creep resistance of the Al2O3 have been improved with the use of other oxide ceramics, among these the Y3Al5O12 (YAG - "yttrium aluminum garnet"), to obtain the Al2O3-YAG composite. The aim of this work is to study the effect of addition of Nb2O5 at low sintering temperatures of the composite, starting from the eutectic composition Al2O3-Y2O3. In this work, the compositions were produced by powder mixtures of Al2O3-Y2O3 and Al2O3-Y2O3-Nb2O5 using high energy ball milling. The green bodies were pressed at 70 MPa and sintered at 1000, 1100, 1200 and 1300°C for 2 h. The materials were characterized by shrinkage and X-Ray Diffraction (XRD) using the Rietveld method. The presence of Nb2O5 does not show any improve neither for the YAG phase formation nor for the shrinkage of the sintered samples in the temperature range studied.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
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