Publication Date:
2016-12-31
Description:
Pressureless sintering of pure γ-Y 2 Si 2 O 7 powders that had been synthesized by a solid-liquid reaction method using Y 2 O 3 and SiO 2 powders with Li 2 O, MgO, and Al 2 O 3 additives was reported. The sintering kinetics of γ-Y 2 Si 2 O 7 powders was analyzed to track details of densification evolution. Apparent activation energies of the densification of γ-Y 2 Si 2 O 7 powders were reported for the first time, which was 57.1, 96.6, and 100.2 kJ/mol for the powders with Li 2 O, MgO, and Al 2 O 3 additives, respectively, indicating that Li 2 O could promote the densification behavior effectively. The flexural strengths as a function of temperature for the γ-Y 2 Si 2 O 7 ceramics with different additives were also investigated. The degradation of high-temperature flexural strength was mainly ascribed to the softening of grain-boundary glassy phase. γ-Y 2 Si 2 O 7 specimens fabricated using the powders with MgO or Al 2 O 3 additives exhibited better high-temperature mechanical properties.
Print ISSN:
0002-7820
Electronic ISSN:
1551-2916
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Permalink
