摘要
Ammonium aluminum carbonate hydroxide（AACH）, the precursor of α-Al2O3, was fabricated with NH4Al（SO4）2 and NH4HCO3 via a precipitation method. During the heat treatment AACH undergoes such a phase transformation process: amorphous（350℃）→γ（700℃）→γ+θ（1050℃）→θ+α （1100℃）→α （1200℃）. Oxides, such as TiO2 sol and MgO sol were introduced into the precursor. Then both the α transformation temperature and the particle sizes of α-Al2O3 are decreased. The microstructures and its surface electronic properties of the powders are modified, and its dispersion property is improved. Doping TiO2 sol grains, AACH completes α phase transformation nearly at 1100℃, its first-order diameter is about 120nm. Doping with MgO sol grains, α phase transformation completes after being sintered at 1100℃.
Ammonium aluminum carbonate hydroxide(AACH), the precursor of α-Al_2O_3, was fabricated with NH_4Al(SO_4)_2 and NH_4HCO_3 via a precipitation method. During the heat treatment AACH undergoes such a phase transformation process: amorphous(350℃)→γ(700℃)→γ+θ(1050℃)→θ+α (1100℃)→α (1200℃). Oxides, such as TiO_2 sol and MgO sol were introduced into the precursor. Then both the α transformation temperature and the particle sizes of α-Al_2O_3 are decreased. The microstructures and its surface electronic properties of the powders are modified, and its dispersion property is improved. Doping TiO_2 sol grains, AACH completes α phase transformation nearly at 1100℃, its first-order diameter is about 120nm. Doping with MgO sol grains, α phase transformation completes after being sintered at 1100℃.
出处
《中国有色金属学会会刊：英文版》
CSCD
2005年第S3期447-451,共5页
Transactions of Nonferrous Metals Society of China
基金
Project(040020392)supportedbytheKeyProgramofScienceandTechnologyofAnhuiProvince
project(20051004)supportedby2005AnnualKeyScientificProgramofHefei
