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Copyright of Journal of Functional Materials / Gongneng Cailiao is the property of Chongqing Functional Materials Periodical Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

MgO-Al2O3-SiO2, glass-ceramics were prepared by a melt-quenching method. The effects of CaO content on crystallization, micro-morphology, flexural strength, thermal expansion coefficient, and dielectric properties were investigated. The activation energy for sintering was calculated based on the Arrhenius model of a constant heating rate. The results showed that since Ca atoms entered into the glass network, CaO addition reduced the softening point and the crystallization temperature of glass effectively and changed the crystallization tendency. Also, CaO doping reduced the sintering activation energy and promoted the sintering process of glass ceramics. The increase of secondary crystal phase (MgAl2Si3O18)0.6 leaded to an increase o f thermal expansion coefficient of the glass-ceramic. Mean while, an increase of flexural strength was related to the increase of bulk density and the internal stress generated by high thermal expansion phase. When the amount of CaO was 3 wt %, the glass-ceramic sintered at 950 °C showed best performances: flexural strength of 152 MPa, thermal expansion coefficient of 3.52 X 10-6 /°C, dielectric constant of 5.89, and dielectric loss of 1.85 X 10-3 . [ABSTRACT FROM AUTHOR]