PREPARATION AND PROPERTIES OF CORUNDUM HCBS
AND CERAMIC CONCRETES.
PART 2. COMPOSITION AND PROPERTIES
OF COMPACTED CERAMIC CONCRETES
Yu. E. Pivinskii
and Pavel V. Dyakin
Translated from Novye Ogneupory, No. 2, pp. 39 – 46, February, 2010.
Original article submitted November 24, 2009.
The effect of the composition of original molding systems and firing temperature on the properties of
= 1.5 mm) and medium grain sized (D
= 4.0 mm) specimens of compacted corundum
ceramic concretes with a corundum-mullite matrix system are studied. Optimum properties (open porosity of
14 – 15%, ultimate strength in compression of 150 – 200 MPa) are achieved in compositions with a matrix
system content of 30 – 35%. A calculation and experimental method is used to determine matrix system po
rosity in ceramic concrete specimens in relation to their composition.
Keywords: ceramic concretes, grain size composition, Andreasen equation, matrix system, filler, porosity, ul-
timate strength in compression.
In the general balance of production of high-alumina ce-
ramic concretes in OAO Pervoural Dinas Plant alongside
ramming and vibration casting materials a significant pro-
portion (about 40%) is occupied by compacted refractories
[1, 5, 10]. Particularly effective among them are mullite-co-
rundum heat-resistant and dense refractories grade
MKTP-85, that have operated very successfully not only in
the working layer of the lining of steel-pouring ladles, but
also in lining many other heating units [5, 7]. The production
efficiency of these refractories is determined by the fact that
in order to mold them there is use of traditional friction
presses, previously used for compacting dinas refractories. It
is entirely probable that an increase in Al
content in these
refractories from 85 – 87 to 90 – 95% with a simultaneous
reduction in the admixture content, present in bauxite, will
make it possible to increase the life of corundum refractories
developed in this study.
SUBSTANCE AND GRAIN SIZE COMPOSITION
OF THE STARTING MOLDING SYSTEMS
A HCBS of mixed composition in the corundum –
VFQG system is used as the matrix system. The preparation
technology and properties of the latter have been considered
in part 1 of the present article.
The refractory filler used was fractionated polydispersed
electrocorundum. For compaction of specimens of fine-
grained ceramic concretes a polyfraction filler is used having
a maximum particle diameter D
= 1.5 mm, and D
medium grain sized filler is 4.0 mm (Fig. 1). The median di-
ameters of particles d
of the filler were 0.4 and 1.0 mm, and
the bulk density was 2.0.and 2.2 g/cm
for curves 1 and 2 of
Fig. 2 respectively.
Refractories and Industrial Ceramics Vol. 51, No. 1, 2010
1083-4877/10/5101-0032 © 2010 Springer Science+Business Media, Inc.
OOO NVF Kerambet-Ogneupor, St Petersburg, Russia.
St Petersburg State Technological Institute (Technical Univer
sity), St Petersburg, Russia.
Fig. 1. Integral curves of grain size distribution of corundum fillers
for preparing fine-grained (1 ) and medium grain sized (2 ) ceramic