STUDY OF ALUMINUM OXIDE POWDER PREPARED
BY CHEMICAL DISPERSION OF ALUMINUM-MAGNESIUM ALLOYS
A. D. Shlyapin,
A. Yu. Omarov,
V. P. Tarasovskii,
and Yu. G. Trifonov
Translated from Novye Ogneupory, No. 6, pp. 63 – 65, June, 2013.
Original article submitted January 22, 2013.
Results are given for petrographic analysis of aluminum oxide powder, prepared by chemical dispersion of
aluminum-magnesium alloys, containing 6 and 12 wt.% magnesium. Powders are washed by vacuum filtra
tion and dried at 60 – 80°C. Heat treatment is performed at 1400°C with soaking for 1 h. Comparative analysis
of the results obtained is also performed, and material phase composition and structure are described.
Keywords: aluminum oxide, vacuum filtration, drying, heat treatment, petrographic analysis, structure, phase
The aspiration for creating new ceramic materials exhib-
iting improved properties has led in the last decades to a
rapid increase in scientific, commercial, and industrial inter-
est in ultrafine powders. In view of this it is important to
study aluminum oxide powder prepared by chemical disper-
sion of aluminum alloys.
ALUMINUM OXIDE POWDER
Chemical dispersion of Al–Mg alloy was accomplished
by treating it with 20% caustic soda solution . The process
of dispersion was carried in a vessel of heat and chemically
resistant glass with continuous heat removal (by means of a
water bath) and mixing:
Al–Mg + NaOH ® residue.
The residue obtained from the mother solution was fil-
tered and washed repeatedly with distilled water by vacuum
filtration using a Buchner funnel and a Bunsen flask. The
volume of water expended in each washing was 1 liter. The
change in medium pH index (residue in the form of a suspen-
sion) after each washing was determined by means of a HI
98108 pH-meter from Hanna Instruments (Germany). The
instrument measurement accuracy was ±0.1 pH unit. The re-
sults obtained are provided in Table 1.
Heat treatment of residue was performed in air at 1400°C
for 1 h. The temperature and time parameters for heat treat
ment were established by experiment. High-temperature ox
ide modifications were achieved entirely at a selected tem
perature for transition of residue hydroxide components .
OF PHASE COMPOSITION AND STRUCTURE
OF ALUMINUM OXIDE POWDER
A preparation immersion method was used to analyze
samples, shown in Table 2. Properties of the main crystalline
Refractories and Industrial Ceramics Vol. 54, No. 3, September, 2013
1083-4877/13/05403-0251 © 2013 Springer Science+Business Media New York
FGBOU VPO Moscow, State Industrial University, Moscow,
ZAO NTTs Bakor, Shcherbinka, Moscow Region, Russia.
TABLE 1. Values of Medium pH Index for Deposition of Al–Mg Alloy Chemical Dispersion Product
Medium pH index after n-fold residue washes (n =0–10)
012 3 45678910
6 13.1 12.9 12.7 12.5 12.0 11.5 10.2 8.3 8.1 7.9 7.7
12 13.1 13.0 12.8 12.3 11.2 10.9 10.6 10.3 10.2 10.1 10.0