A simple procedure to prepare spherical {alpha}-alumina powders

Journal Article · Thu Apr 02 04:00:00 EDT 2009 · Materials Research Bulletin

OSTI ID:21199726

Hongyu, Liu ^[1]; Zhihong, Gan; Yuan, Lin ^[1]

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1. State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China)

Spherical {alpha}-alumina powders were prepared by the controlled hydrolysis of aluminum isopropoxide in a hydrolysis system consisting of octanol and acetonitrile. Diverse solvents to dissolve reactant formed diverse hydrolysis systems and affected particle shape of {alpha}-alumina powders. The precursors crystallized to {gamma}-alumina at 1000 deg. C and converted to {alpha}-alumina at 1150 deg. C without intermediate phases. The particle morphology of precursor was retained after it crystallized to {alpha}-alumina. The heating rate influenced the particle shape and the state of agglomeration during calcination process. The thermal properties of the precursors were characterized by thermal gravimetric and differential thermal analysis. X-ray diffraction technique was used to confirm the conversion of crystalline phase of alumina powders from amorphous to {alpha}-phase. Transmission electron microscopy was used to investigate the morphologies and size of the precursors and products.

• OSTI ID: 21199726
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 4 Vol. 44; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACETONITRILE
AGGLOMERATION
ALUMINIUM OXIDES
CALCINATION
CERAMICS
DIFFERENTIAL THERMAL ANALYSIS
HEATING RATE
HYDROLYSIS
MORPHOLOGY
PARTICLES
SOL-GEL PROCESS
SPHERICAL CONFIGURATION
TEMPERATURE RANGE 1000-4000 K
THERMAL GRAVIMETRIC ANALYSIS
THERMODYNAMIC PROPERTIES
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION