SCIENTIFIC RESEARCH AND DEVELOPMENT
PREPARATION AND SOME PROPERTIES OF SINTERED
ALUMINOSILICATE CERAMIC BASED ON HCBS. PART II
Yu. E. Pivinskii,
P. V. Dyakin,
D. V. Gorbachev,
and S. A. Strel’tsov
Translated from Novye Ogneupory, No. 3, pp. 145 – 154, March, 2013.
Original article submitted December 11, 2012.
Sintering and some properties of fine aluminosilicate ceramic, prepared on the basis of HCBS from broken
porcelain electric insulator and pearlite, are studied. After firing at 1000 – 1500°C ceramic has open porosity
of 1 – 8%, and ultimate strength in bending and compression of 45 – 65 and 350 – 500 MPa respectively.
Compared with traditional fine ceramic materials, such as porcelain, semi-porcelain, hard faience, and majol
ica, in the new technology comparable properties are achieved with significantly (by a factor of 3 – 5) lower
overall shrinkage and a reduced (by 150 – 200°C) firing temperature. Possible areas are indicated for imple
menting HCBS-technology in the field of production, not only for traditional fine ceramic, but also
fine-grained structural, and artistic architectural ceramics.
Keywords: HCBS, casting, sintering, porosity, shrinkage, strength, thermal expansion, fine ceramics, artistic
SINTERING AND SOME PROPERTIES OF
Basic research has been carried out using specimens pre
pared from two separately prepared suspensions, i.e., based
on broken ceramic, and pearlite. Castings for study were pre
pared both from original suspensions (HCBS), and also from
binary mixtures with a pearlite content (by weight) from 10
to 75%. Properties studied for the original suspensions or
castings based on them, and materials after firing differ con
siderably. Individual tests were carried out on castings pre
pared on the basis of mixed HCBS of combined grinding
with addition of pearlite primer suspension.
Heat treatment and firing of cast specimens after prelimi
nary drying at 110 – 150°C was performed in a laboratory
electric furnace by a rapid regime with isothermal soaking
for 1 h at 400, 600, 800, 900, 1000, 1050, 1100, and 1150°C
with a heating rate of 300°C/h. The overall duration of the
controlled firing process even for the maximum temperature
did not exceed 5 h. After 1 h exposure at the maximum (pre-
scribed) temperature specimens were spontaneously cooled
in the furnace. Then the following were determined: weight
loss, open porosity P
, apparent density, r
strength in bending s
and compression s
(400 – 800°C) and fired (900 – 1150°C) specimens.
It is a feature that the main properties of specimens of all
compositions studied are mainly their shrinkage indices dur
ing heat treatment (firing). The amount of shrinkage depends
on specimen composition and firing temperature. Apart from
these properties thermal expansion and the structure of mate
rials obtained were also studied.
Comparative data are presented in Fig. 1 for the change
in linear shrinkage Dl with isothermal heating of castings
based on pearlite and mixed composition. For specimens
based on pearlite marked shrinkage is noted at above 200°C,
and at 600 – 700°C it reaches 0.8 – 0.9%. It has been estab
lished that heating of pearlite castings in the range
200 – 800°C is accompanied by significant (3.5 – 4.0%)
weight loss as a result of removal of chemically-bonded wa
ter. Shrinkage commences on heating above 800°C, caused
by material sintering. This develops particularly intensely in
the range 900 – 1000°C. Total casting sintering, correspond
ing to about 7% linear shrinkage, occurs at 1100°C.
Refractories and Industrial Ceramics Vol. 54, No. 2, July, 2013
1083-4877/13/05402-0120 © 2013 Springer Science+Business Media New York
Part I of the article was published in Novye Ogneupory, No. 2,
30 – 41 (2013).
OOO NVF Kerambet-Ogneupor, St. Petersburg, Russia.
GOU VPO St Petersburg State Technological Institute (Technical
University), St. Petersburg, Russia.
OOO VKVS-Tekhnologii, Lipetsk, Russia.