SILICON CARBIDE REFRACTORY CASTABLES
V. A. Kamenskikh,
I. D. Kashcheev,
N. A. Mityushov,
A. A. Gulyaev,
M. V. Kotova,
A. S. Kiselev,
and S. A. Leshkeev
Translated from Novye Ogneupory, No. 12, pp. 36 – 39, December, 2005.
Original article submitted April 18, 2005.
Optimum formulations for castables intended for different service conditions are proposed. Silicon carbide
castables containing ultradisperse particles of cement, silica fume, and electrofused corundum are developed.
The castables do not weaken on heating and display superior operational properties: the compressive strength
is 40 – 80 MPa at sintering temperature 400°C and 50 – 85 MPa at 1300°C, the strain onset temperature under
a load of 0.2 MPa is 1700 – 1510°C; thermal stability (1300°C – water) is better than 45 heating/cooling cy
cles (1300°C – water); no change in linear and volume dimensions was observed on heating. The newly-de
veloped castables can find application in various sectors of industry, in particular, as the refractory material for
the lining of Whiting furnaces and porcelain kilns.
Under the new economy, survival of the refractory indus-
try depends on the ability of the manufacturer to promptly re-
spond to requests and concerns of the market, and to improve
the production technology to meet consumers’ needs. Under
these conditions, there is a consistent tendency among fo-
reign manufacturers to increase the share of unshaped
castables in the overall balance of refractory materials. The
relatively low labor input and ease of fabricability in the
manufacture of refractories are the factors that have deter
mined the ever-increasing use of unshaped refractories for
the lining of intermediate and pouring ladle, for preparation
of gunning mixes, etc. In recent years, the performance cha
racteristics of unshaped refractory materials and linings
based on them are becoming increasingly competitive with
those of shaped components. The demand for unshaped and
nonfired refractories, unlike that for shaped and fired materi
als, is constantly on the rise. Development and fabrication of
vibrocast monolithic linings and components is another im
portant field for creative efforts in the refractory industry.
A survey of the literature has shown that refractory
castables of corundum, aluminosilicate, and spinel composi
tion have become widespread in the refractory industry. To
the best of our knowledge, no data on the production of a
new generation of refractory castables based on silicon car
bide could be found in the domestic literature whereas these
materials are commercially available from foreign manufac-
Silicon carbide refractories, owing to their specific prop-
erties, have found wide application in different sectors of in-
dustry. Silicon carbide refractories, owing to their high heat
conductivity, have found widespread use in the manufacture
of muffles, furnace bottoms, and recuperators. The high me
chanical strength and abrasive resistance over wide a tempe
rature range make silicon carbide refractories a perfect mate
rial for fabrication of parts and components intended for ser
vice under heavy-duty conditions including low tempera
tures: guide rails and rods, cyclone lining, dust collectors,
pipelines, troughs and other facilities subjected to intense
abrasion, furnace cars, etc. Silicon carbide, owing to its spe
cific chemical properties, proved to be an effective material
for heating and processing facilities in the nonferrous metal
lurgy and chemical industry.
In developing the formulation and technology for low-
cement silicon carbide refractory, the major requirements
taken into consideration were: (i) optimum grain composi
tion to ensure the highest possible dense structure; (ii) com
pound additives of appropriate composition, and (iii) mini
mum amount of mixing water (using advanced plastisizers)
to provide the needed rheological characteristics.
The filler used in this study was black silicon carbide
powder of different dispersities (State Standard GOST
26327) containing 96 – 97% SiC.
Refractories and Industrial Ceramics Vol. 46, No. 6, 2005
1083-4877/05/4606-0412 © 2005 Springer Science+Business Media, Inc.
Ural State Technical University (UGTU – UPI), Ekaterinburg,