REFRACTORY CONCRETES AND COATINGS
BASED ON MODIFIED BINDER SUSPENSIONS
Yu. N. Trepalina
Translated from Novye Ogneupory, No. 6, pp. 54 – 56, June, 2010.
Original article submitted October 1, 2009.
The process of manufacturing protective coatings by means of deposition of aqueous suspensions is distin
guished by the simplicity of the technological process and the low temperature at which it is realized. Phos
phate-containing binders and concretes based on these types of binders increase the resistance of the particular
material to corrosive media. Through their use it is possible to increase the service life of refractories.
Keywords: mechanical activation, corundum, joint grinding, phosphate-containing concrete, resistance to
The basic problem in the refractory industry is to realize
intensive development of ecologically clean, waste-free tech-
nologies that yield a savings in raw materials and manpower.
The efficient consumption of refractories may be achieved
through an increase in the technological level of the produc-
tion process and the use o less expensive materials, for exam-
ple, refractory concretes. The use of the small articles that
are now being produced has decreased the service life of fur-
nace linings because of the large number of seams and has
made it difficult to mechanize the process.
The continuing improvement in metallurgical and other
high-temperature processes has made it necessary to expand
the range of refractories and to create new refractory materi
als. The design of the structure of refractories, a process that
presupposes the widespread use of unfired concrete and
unmolded mixtures, represents a promising trend in efforts
aimed at improving the quality and increasing the operating
properties of refractories .
Studies that have performed in recent years have made it
possible to define the direction of research into energy- and
resource-conservation technologies with the use of mechani
cal activation. In the course of studying the processes that oc
cur in joint grinding, it has been found that a colloidal com
ponent in the form of microscopic particles of a crystalline
substance form in joint grinding. Suspensions that have been
activated by a mechano-chemical method are distinguished
by thixotropic-type flow and binding power, which has made
it possible to apply them as the binding component of unfired
refractory concretes, refractory articles, and protective coat
The high degree of durability of the types of concrete
used for the lining of the iron-foundry spouts of blast fur-
naces is achieved principally by virtue of their nonwettability
by molten iron and a reduction in the oxidizability of the car-
bon part of the compound. The oxidizability of of the carbon
part of the compound for the spouts may be substantially re-
duced through the deposition of protective coatings on the
compound by means of concrete spraying . The impor-
tance of protective coatings on refractories is due to the wide
range of applications possible. There exist coatings that are
chemically durable, anti-burn-on, gas-shielding, etc. The ser
vice life of a coating depends on the operating conditions and
is from a few seconds to several days. In each particular case
the choice of protective coatingmust be made as a function of
the nature of the corrosive medium and the nature of the ma
terial which is to be coated. The coating must be refractory
and resistant to sharp oscillations of tempeature and mechan
ical actions .
Of all the numerous methods of forming protective coat
ings the most widespread is that of depositon of aqueous sus
pensions on the surface of refractory materials, a method dis
tinguished by comparative simplicity of the technological
process and low temperature of realization. The suspensions
that have been deposited on the refractory surface are sub
jected to drying or heat treatment (high-temperature
sintering). To maintain the resistance of the suspensions, it is
recommended that an optimal quantity of a colloidal compo
nent be added to the suspension . Clays, kaolin (Mg(OH)
added at a rate of 4 – 8% of the total content of the solid
phase, may serve as such components.
With the addition of 10% raaw milled technical alumina,
corundum magnesium-phosphate bonding concretes are then
distinguished by elevated density, strength, and thermal sta
Refractories and Industrial Ceramics Vol. 51, No. 3, 2010
1083-4877/10/5103-0210 © 2010 Springer Science+Business Media, Inc.
V. G. Shukhov State Technological University, Belgorod, Russia.