HEAT-RESISTANT CORUNDUM CONCRETE
REINFORCED WITH ALUMINUM OXIDE FIBERS SYNTHESIZED
WITHIN A MATRIX DURING FIRING.
PART 1. HEAT RESISTANCE OF HIGH-TEMPERATURE MATERIALS
AND MEANS OF IMPROVEMENT
V. N. Sokov
and S. D. Sokova
Translated from Novye Ogneupory, No. 5, pp. 37 – 40, May, 2014.
Original article submitted March 12, 2014.
Good corundum concrete thermomechanical properties may be obtained by creating a matrix with corundum
fibers distributed uniformly within it. Fibers are synthesized during the best selected heat treatment regime for
a composite containing special fibers.
Keywords: corundum concrete, heat resistance, reinforcement, composite materials, matrix, stress concentra-
tion, fiber preparation methods.
Rapid development of science and technology, and intro-
duction of new manufacturing processes require a consider-
able amount of high quality refractory materials, which im-
pose new improved specifications. In order to provide oper-
ating capacity for structures, often it appears to be insuffi
cient to obtain only mechanical strength with complex forced
and thermal loads. It is necessary that a selected structural
material, exhibiting a capacity to resist corrosive chemical
action of an atmosphere, has good thermophysical proper
ties, erosion resistance, and answers a number of other speci
fications determining operating capacity criteria during pro
longed operation, and consequently affecting technical and
economic indices of high-temperature processes.
Therefore questions of finding and developing new re
fractory materials capable of resisting thermal action, are
currently very important, since they often play a definitive
role in creating a new type of device and installation in many
branches of industry. In ammonia synthesis and methane
conversion in a highly productive converters a gas mixture at
the inlet to a converter contains water vapor, hydrogen, car
bon oxide, whose reaction with iron and silicon oxides con
tained within a lining leads to significant stresses in an
equipment lining and its subsequent breakdown. In addition,
liberated silicon is deposited on thermal insulation pipe
walls, installed after the converter, and leads to failure.
Corundum objects are some of the best highly refractory,
chemically stable materials, exhibiting strength and dielec
tric properties, and also a number of specific characteristics,
i.e., significant creep resistance and simultaneously good re
sistance to reduction at elevated temperature. However, the
thermal shock resistance of corundum materials is low. This
is explained by a significant LTEC and as a consequence
with high thermal strains causing stresses in a material dur
ing heating and cooling.
The aim of this research is development of technology
for reinforced corundum concrete with good thermomechan
ical properties intended for structural elements of large in
dustrial heating units, operating in oxidizing and reducing
gas atmospheres with an operating temperature up to
1700ºC. One of the known and most effective methods for
improving thermal shock resistance is reinforcement of re
fractory materials with fibers and lamellar inclusions. These
inclusions are “useful defects”, which slow down and even
stop crack propagation, blunting their tips, and on the other
hand if they exhibit high strength compared with matrix ma
terial, they maintain composite material strength preventing
catastrophic structural failure.
Refractories and Industrial Ceramics Vol. 55, No. 3, September, 2014
1083-4877/14/05503-0223 © 2014 Springer Science+Business Media New York
FGBOU VPO Moscow State Building University, Moscow, Russia.