STUDY OF COMPACTION OF HIGH-ALUMINA CERAMOCONCRETES.
4. THE EFFECT OF FIRING TEMPERATURE ON THE PROPERTIES
OF A MATRIX SYSTEM AND ON CERAMOCONCRETE
Yu. E. Pivinskii,
Pavel V. Dyakin,
and Petr V. Dyakin
Translated from Novye Ogneupory, No. 10, pp. 29 – 37, October, 2006.
Original article submitted May 4, 2006.
The effect of firing temperature on variations of the linear sizes, open porosity, apparent density, and mechani
cal strength both of the matrix system and of industrially produced ceramoconcretes based on a high-con
centrated ceramic binding suspension (HCBS) containing 90% bauxite and 10% quartz glass is investigated.
Experimental materials based on HCBS of density 2.62 – 2.77 g/cm
= 0.65 – 0.70) with the content of
particles of size below 1 ìm varying from 4 to 15% encompass the whole spectrum of quantitative parameters
of initial suspensions that are prescribed or possible in industrial production. Samples based on a bauxite
HCBS with 10% highly disperse quartz glass, as well as samples of ceramoconcrete consisting of the same
HCBS (35%) and a bauxite-based refractory filler, were obtained by compaction, heat-treated and fired in the
interval of 100 – 1420°C. Perceptible sintering accompanied by shrinkage and significant strengthening of the
material is registered in the interval of 1000 – 1250°C. A certain expansion and loosening of the material is
observed in the range of 1300 – 1400°C due to intense mullite formation. Significant sintering and strengthen-
ing is achieved by protracted firing at 1400 – 1420°C. Comparative analysis of the properties of the matrix
system and ceramoconcrete has established that, other terms being equal, ó
of ceramoconcrete amounts to
40 – 50% ó
of the matrix system.
In our previous studies [1 – 3], the properties of all con-
sidered materials were usually determined based on three
particular firing temperatures. However, considering then
that the process of mullitization is very intense in the consid
ered systems, it becomes necessary to study in more detail
the effect of firing temperature on the properties of both the
matrix (binding) system and ceramoconcrete. Accordingly,
compacted samples based on the bauxite high-concentration
ceramic binding suspension (HCBS) with 10% highly dis
persed quartz glass , as well as samples of ceramoconcrete
consisting of the same HCBS (35%) and a refractory filler
based on densely sintered bauxite (89% Al
) with particle
sizes 0.1–3mm(65%), were heat-treated in a wide temper
ature range (from 100 to 1420°C). The initial samples were
three industrially produced HCBS samples (a ball mill of ca
pacity 3.2 m
), which differed significantly in their density
and degree of dispersion, which can be seen in Fig. 1. The
HCBS corresponding to curve 1 in Fig. 1 has the minimal
density and a relatively coarse granular composition, where
as the HCBS corresponding to curve 3 has the maximal den
sity and the maximal content of finely dispersed fractions.
Curve 2 in Fig. 1 corresponds to the HCBS with intermediate
parameters. The considered ranges of fundamental HCBS
properties, namely a density of 2.62 – 2.77 g/cm
0.65 – 0.70) and a content of particles below 1 ìm ranging
Refractories and Industrial Ceramics Vol. 47, No. 5, 2006
1083-4877/06/4705-0302 © 2006 Springer Science+Business Media, Inc.
NVF “Kerambet-Ogenupor” Co., Russia; St. Petersburg State
Technological Institute (Technical University), Russia.
10000 1000 100 10 1 0.1
Particle diameter, mì
Fig. 1. Integral curves of the granular distribution of solid-phase
particles in bauxite HCBSs of different densities, g/cm
: 1, 2.62;
2, 2.64; 3, 2.77; 4, molding system with the filler.