EFFECT OF CARBON TYPE ON UNMOLDED
REFRACTORY MATERIAL PROPERTIES.
PART 1. STUDY OF CARBON-CONTAINING
MATERIAL STRUCTURE AND PROPERTIES
I. D. Kashcheev,
K. G. Zemlyanoi,
and V. M. Ust’yantsev
Translated from Novye Ogneupory, No. 8, pp. 10 – 22, August, 2016.
Original article submitted May 6, 2016.
Microstructure, phase composition, and physicochemical properties of domestic and imported carbon materi
als used in refractory concretes are studied. It is established that graphites of different origin have different
surface morphology, crystal lattice structure, and wetting capacity.
Keywords: carbon, concrete, corrosion resistance, wettability, structure.
Carbon-containing unmolded refractories are used in the
foundry industry (main blast furnace trough lining, etc.). Due
to the increasing demand for more energy effective and eco-
logically clean materials producers concentrate their efforts
on structures made from refractories with improved proper
The advantages of introducing carbon into refractory ma
terials are generally known [1, 2]. However, difficulties con
nected with distribution of this form of raw material in an
aqueous medium is one of the main barriers for development
and further use of carbon in unmolded refractory materials,
in particular concretes. Another factor retarding use of car
bon in unmolded refractories is low oxidation resistance
above 600°C [2, 3].
Graphite (normal or synthetic), carbon black, pitch, coke,
polymer resins, serve as the main sources for introducing
carbon into unmolded refractories. These materials differ
considerably with respect to properties . Consequently, a
study of the possibility of introducing graphite into concrete
is a prospective task [4, 5]. Possible approaches have been
suggested for resolving the problem connected with wetting
capacity of carbon-containing materials with water: use of
surfactants (SAS) and graphite surface modification by ap-
plying oxide or non-oxide coatings (chemical deposition
from a gas phase [2 – 5], use of high-speed impact , by
means of sol-gel technology [7 – 11], etc.), and use of or-
ganic liquids such as phenol resins for MgO-C-refractories
[12, 13]. However, oxide grains are difficult to disperse in or
ganic media, and in order to obtain optimum rheological
properties a considerable volume of resin with low viscosity
is necessary, and this is connected with an increase in poros
ity and overall cost of the refractories developed. Thus, in
spite of numerous studies, aqueous systems, based on hy
draulic binders, are mainly considered preferable in the ma
jority of compositions of carbon-containing unmolded
Although amorphous carbon (carbon black, coke, pitch)
is best dispersed in water, its resistance to oxidation is less,
which leads to a significant reduction in mechanical strength
and corrosion resistance of a refractory at high temperature
[14, 15]. Low oxidation reaction is possible for carbon-con
taining components with addition of antioxidants: metals ad
their alloys (Al, Si, Mg, Al–Mg), carbides (SiC, B
), borates (ZrB
), and some other compounds.
Much work has been devoted to evaluating the efficiency of
these additives and their reaction with water, oxygen, CO
and other phases [16 – 22], which points to a requirement for
observing care with adding antioxidants to concrete mixes
Refractories and Industrial Ceramics Vol. 57, No. 4, November, 2016
1083-4877/16/05704-0342 © 2016 Springer Science+Business Media New York
FGAOU VPO Ural Federal University, Ekaterinburg, Russia.