PREPARATION AND PROPERTIES
OF CORUNDUM HCBS AND CERAMIC CONCRETES.
PART 3. CASTING AND VOLUME CONSTANCY
OF CERAMIC CONCRETES
Yu. E. Pivinskii
and Pavel V. Dyakin
Translated from Novye Ogneupory, No. 3, pp. 27 – 34, March 2010.
Original article submitted December 23, 2009.
Vibration casting and casting from a self-spreading mix with an original moisture content of molding systems
of 3.8 – 4.2% are used to prepare coarse-grained (D
= 10 mm) and medium-grained (D
= 3 mm) corun
dum ceramic concretes with a corundum-mullite matrix system. Depending on the heat treatment temperature,
the amount of their open porosity is 11 – 15%, and the ultimate strength in compression reaches 160 MPa.
Both cast and compacted ceramic concretes have high volume constancy during heating or firing, and also in
service. Linear shrinkage does not exceed 0.2 – 0.5%.
Keywords: ceramic concretes, vibration casting, casting from a self-spreading mix, volume constancy, matrix
In the previous part
of the present article results were
provided for a study of compaction that is quite promising in
the technology of numerous materials prepared on the basis
of HCBS. Features established during a study of this process
make it possible to predict the properties not only of molded,
but also unmolded ceramic concretes, used in the form of
ramming (pneumatic ramming) mixes [1, 27]. It has been es
tablished by experiment that the degree of compaction
achieved roughly corresponds to the apparent density of
compacts under a pressure of P = 150 – 200 MPa. As applied
to ceramic concrete technology there is no less interest in
their vibration casting (vibration laying) and casting from
self-spreading (without application of vibration) mixes.
CASTING MOLDING SYSTEMS AND PROPERTIES
OF CAST CERAMIC CONCRETES
Preliminary studies have been carried out for the choice
of original grain size composition and content of the matrix
system applied to preparation of coarse-grained (D
and medium-grained (D
= 3.0 mm) ceramic concretes,
molded by vibration casting in inactive (metal) molds
[28, 29] or by casting from self-spreading mixes.
The grain size composition of the original molding sys-
tem for preparing specimens of coarse-grained ceramic con-
crete, molded by casting from self-spreading mixes and vi
bration casting in metal molds, is shown in Fig. 1. The start
ing mix has a significant (31%) content of coarse corundum
filler (6 – 10 mm) and about 40% of polyfraction filler with a
particle size of 0.1 – 6 mm. The optimum content of the ma
Refractories and Industrial Ceramics Vol. 51, No. 2, 2010
1083-4877/10/5102-0088 © 2010 Springer Science+Business Media, Inc.
OOO NVF Kerambet-Ogneupor, St. Petersburg, Russia.
St Petersburg State Technological Institute (Technical Univer
sity), St Petersburg, Russia.
Published in Novye Ogneupory No. 2, 39 – 46 (2010).
Fig. 1. Integral curve of particle grain size distribution in a molding
system for preparing coarse-grained corundum ceramic concretes
= 10) by casting and vibration casting: a) common curve;
b ) matrix system curve.