CERAMIC OBJECTS FOR DISPENSING MOLTEN ALUMINUM ALLOYS
V. T. Shmuradko,
O. V. Roman, A. F. Il’yushchenko,
L. V. Sudnik,
and N. V. Kirshina
Translated from Novye Ogneupory, No. 1, pp. 28 – 30, January 2014.
Original article submitted July 22, 2013.
Preparation of special aluminum alloys and refractories conforming to them are considered from the point of
view of physicochemical processes and aluminum metallurgy mechanisms, functional capacity of melting and
casting equipment and a ceramic lining, making it possible to control casting structural and chemical parame
ters during their preparation. Compositions and production solutions are developed for preparing shaped re
fractory lining objects based on cement-free ceramic concretes.
Keywords: ceramic objects, melting and casting equipment, dispensing assembly, ceramic concretes, highly
concentrated binder suspensions (HCBS).
Status of the question. Comprehensive solution of the
problem of obtaining special structural aluminum alloys and
lining materials for heating units is closely connected on one
hand with physicochemical processes of aluminum metal-
lurgy, i.e., melting mechanisms, preparation and introduction
of master alloys into a melt, casting, dispensing, and crystal-
lization, and on the other hand with the functional capacity of
melting and casting equipment making it possible to distin-
guish and effectively perform the tasks posed in each produc-
tion stage of a metallurgical process, thereby providing prep
aration of castings of prescribed quality. For effective imple
mentation of the task stated it is necessary to use refractory
lining objects in melting and casting equipment with stable
high values of corrosion and erosion resistance, thermal
shock resistance, physicochemical and other properties .
Starting materials and principles for creating a lining.
Considering the chemical activity of aluminum alloys, high
specifications laid down for the properties created for alumi
num-magnesium alloys, the most effective composite com
ponents in manufacturing linings of melting, dispensing,
crystallizing units of heating equipment, corundum pow
der, corundum-spinel (Al
(MgO + Al
) with additives of grain size composition of
0 – 5 mm, and also highly concentrated ceramic binder sus
pensions (HCBS), prepared by liquid grinding of identical
powder compositions in ceramic grinding units, are adopted.
Self-hardening ceramic mixes have been developed from
powder systems, from which shaped lining objects are pre-
pared (self-hardening at 24 and 350°C), and this has made it
possible to achieve stable structure and phase formation in
lining materials during operation. During service object ma-
terial retains values achieved for structural-chemical and
phase relationships, satisfying thermophysical, physico-
mechanical, and other properties . According to , and
research carried out on the basis of corundum and corun
dum-spinel powders with complexes (MgO + Al
), and by
means of additions to the ceramic concretes developed, flexi
ble structure-phase formations have been created with a ca
pacity in object material (in a thermodynamic regime) to
change and conform with each other such indices as thermal
conductivity, chemical stability, LTEC, combining thereby
within objects structural thermal shock resistance and corro
sion resistance, temperature for the start of deformation un
der load, and mechanical strength. In this case one of the
leading roles pertains to spinels, providing high chemical re
sistance in refractories to action of molten metals under
high-temperature conditions .
In order to improve service properties of a lining addi
tives are used in the form of colloidal systems based on alu
mina and silica, which as a source of nanosize superactive
provide structural strengthening of
ceramic concretes. This has made it possible to exclude CaO
from their composition, which as a cement-forming compo
nent worsens corrosion and deformation properties of
refractories at high temperature . In addition, spinel-form
Refractories and Industrial Ceramics Vol. 55, No. 1, May, 2014
1083-4877/14/05501-0023 © 2014 Springer Science+Business Media New York
Autonomous Cost-Accounting Structural Sub-Section “Scien
tific-Research Institute of Pulsed Processes with Test Produc
tion,”, Minsk, Belarus Republic.
State Scientific-Production Association of Powder metallurgy,
Minsk, Belarus Republic.