STUDY ON SYNTHESIS AND DENSIFICATION OF NON-STOICHIOMETRIC MAGNESIUM ALUMINIUM SPINEL
J. DUAN1, X. WANG1, Г.Р. КАРАГЕДОВ2, H. GAO1, and J. YANG3
1School of Materials Science and Engineering, Dalian Jiaotong University, Dalian (China)
E-mail: wangxh@djtu.edu.cn
2Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russia)
E-mail: garik@solid.nsc.ru
3State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing (China)
E-mail: taoci@djtu.edu.cn
Ключевые слова: magnesium aluminium spinel, synthesis, powder, performance, magnesium aluminium spinel, synthesis, powder, performance
Страницы: 305-311
Аннотация
MgO•nAl2O3 powder (n = 1, 1.25, 1.5, 1.75, 2.0, 2.5) was prepared by the bimetal alkoxide hydrolysis method. The effects of changes of aluminium content on material phase, particle size, morphology, infrared transmittance, and ceramic densification were studied. The results show that the MgO•nAl2O3 (n ≤ 2) powder forms a pure phase of magnesium-aluminium spinel at 1200 °C. When n is 2.5, the characteristic peak of Al2O3 appears. The particle size of powder gradually increases with an increase of n value. There were significant differences in the densification of powders with a various of magnesium/aluminium ratio. The density of samples varies greatly with the sintering temperature. When the sintering temperature is between 1200 and 1400 °C, there are no obvious changes. The density is found to be 3.45 g/cm3 at the sintering temperature of 1400 °C. When n is of 1.25 and 1.5, the sample density increases with an increase of sintering temperature, reaching 3.46 g/cm3 at 1550 °C. The powder with ball milling has a better sintering performance, the density of the MgO•1.5Al2O3 powder with ball milling is 3.448 g/cm3 at the sintering temperature of 1600 °C, which is 2.5 % higher than that of the non-ball-milled sample at the same temperature.
DOI: 10.15372/KhUR2019138 |