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Effect of Alkali Metal Oxide Addition on the Sinterability of MgO–B 2 O 3 –Al 2 O 3 Glass–Al 2 O 3 Filler Composites
Author(s) -
Okamoto Masahide,
Kodama Hironori,
Shinozaki Kazuo
Publication year - 2008
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2008.02263.x
Subject(s) - sintering , materials science , composite number , thermal expansion , alkali metal , composite material , crystallization , dielectric , flexural strength , porosity , oxide , mineralogy , metallurgy , chemical engineering , chemistry , optoelectronics , organic chemistry , engineering
The sintering of a composite of MgO–B 2 O 3 –Al 2 O 3 glass and Al 2 O 3 filler is terminated due to the crystallization of Al 4 B 2 O 9 in the glass. The densification of a composite of MgO–B 2 O 3 –Al 2 O 3 glass and Al 2 O 3 filler using pressureless sintering was accomplished by lowering the sintering temperature of the composite. The sintering temperature was lowered by the addition of small amounts of alkali metal oxides to the MgO–B 2 O 3 –Al 2 O 3 glass system. The resultant composite has a four‐point bending strength of 280 MPa, a coefficient of thermal expansion (RT—200°C) of 4.4 × 10 −6 K −1 , a dielectric constant of 6.0 at 1 MHz, porosity of approximately 1%, and moisture resistance.