RESEARCH IN THE FIELD OF PREPARING MOLDED
AND UNMOLDED REFRACTORIES BASED ON HIGH-ALUMINA HCBS.
PART 4. EFFECT OF REFRACTORY CLAY ADDITIONS ON PROPERTIES
OF COMPOUND COMPOSITION HCBS, CASTINGS,
AND MATERIALS BASED ON THEM
Yu. E. Pivinskii
and P. V. Dyakin
Translated from Novye Ogneupory, No. 2, pp. 25 – 33, February 2016.
Original article submitted September 2, 2015.
Examples are provided of the efficiency of adding refractory clays in HCBS technology and ceramic con
cretes. Properties of castings prepared by slip casting based on HCBS of composite composition in bauxite –
very fine quartz glass (VFQG), and additions of refractory clay (1 – 10%) are studied. The effect of continu-
ous nonisothermal heating up to 1500°C on specimen linear dimensions is studied by means of a high-temper-
ature dilatometer. Data obtained are compared with specimen apparent porosity after isothermal firing with
soaking for 1 h in the range 800 – 1500°C. Maximum linear shrinkage with nonisothermal heating and mini-
mum value of apparent porosity after isothermal firing correspond to the range 1200 – 1500°C. Maximum in-
dices are noted at 1500°C for both specimen growth and also porosity due to occurrence of secondary
Keywords: HCBS, VFQG, bauxite, refractory clay, mullite, nonisothermal heating, isothermal firing, linear
shrinkage, specimen growth, secondary mullitization, artificial and natural ceramic binders, nanostabilization.
For the last twenty years in OAO Dinur in association
with OOO NVF Kerambet-Ogneupor new industrial technol
ogy and assimilation of large-scale production of different
forms of highly efficient molded and unmolded refractories
have been developed for the first time in Russia, prepared on
the basis of HCBS with a predominant content of bauxite as
their matrix system and different refractory fillers: bauxite,
electrocorundum, silicon carbide, and mixtures of them,
[1 – 12]. A significant proportion of this production concerns
concrete mixes for monolithic lining of blast furnace troughs
(trough mixes) and also production of shaped refractories in
the form of nesting blocks, burner stones, and MKTP-85 ob
jects. Depending on the form of refractories and method of
molding mix formation for their preparation, the content of
matrix system (HCBS) is 25 – 35% (dry weight). For
plasticisation of molding mixes additives of very fine refrac
tory clay are added in an amount of 1 – 2% (vibration-cast
mixes, static pressing) or up to 3% (vibration tamping of
ramming mixes). Refractory clay is within the composition
of a ceramic concrete matrix system, and the content within
them depending on molding method may vary within the
limits of 3 – 10% [5, 7, 9, 13].
The task has been set in the current series of work of op
timizing refractory clay additive content and studying their
effect on different properties of both the matrix system and
also ceramic concretes.
REFRACTORY CLAYS AND THEIR EFFICIENCY
IN HCBS AND CERAMIC CONCRETE TECHNOLOGY
Clays have been considered as natural ceramic binders
(NCB) in a monograph [14, p. 236] in contrast to HCBS as
artificial ceramic binders (ACB). From comparison of the
relative content within it of clay and HCBS it was concluded
Refractories and Industrial Ceramics Vol. 57, No. 1, May, 2016
1083-4877/16/05701-0070 © 2016 Springer Science+Business Media New York
Parts 1 – 3 of the article published in Novye Ogneupory Nos.
8,10, and 12 (2015).
OOO NVF Kerambet-Ogneupor, St. Petersburg, Russia.
FGBOU VPO St. Petersburg State Technological University
(Technical University), St. Petersburg, Russia.