MEASURING THE HIGH-TEMPERATURE STRAIN
AND CREEP IN NONFIRED REFRACTORIES
U. Sh. Shayakhmetov,
V. S. Bakunov,
I. M. Valeev,
and V. R. Bikbulatov
Translated from Novye Ogneupory, No. 4, pp. 121 – 125, April, 2006.
Original article submitted November 2, 2005.
Instrumentation and methodology for the experimental study of high-temperature strain and creep under load
in phosphate-bonded nonfired refractories are described. Results for nonfired aluminosilicate, corundum, sili
con nitride, and other refractory composites are reported.
At present, nonfired refractories occupy a prominent
place among available fire-resistant materials, and a major
concern for technologists is further improvement of the ma-
terial properties. In our opinion, efforts should primarily be
focused on the high-temperature deformation under operat-
An adequate methodology in the deformation study of
nonfired composites, in particular, phosphate-bonded ones, is
sadly lacking. It is far from clear which guiding criteria
should be employed in the design of instrumentation for
measuring deformation, what should be the experimental
methodology and technique for experimental data process
ing. Recommendations available in the literature give little
(if any) on what specific factors should be accounted for in
the study: when heated, the material undergoes deformation
frequently accompanied by chemical transformations, forma
tion of new phases, phase transitions, sintering effects, etc.
All these effects can occur under creep strain conditions un
der the action of an external mechanical load.
At the BashNIPIstrom, instrumentation and methods
have been developed to study experimentally the high-tem
perature strain under load and creep in phosphate-bonded
nonfired refractories; the instruments used were those rec
ommended by the Russian Standard GOST 4070. The de
signed experimental setup (based on a series-produced in
strument) made it possible to conduct tests at temperatures
up to 1550°C and loads up to 5 MPa under uniaxial loading
conditions [1, 2]. The “end effects” were excluded from
measurement results, that is, changes in linear dimensions
(gauge length) of the specimen were recorded under uniform
stress conditions only. To minimize the buckling, the height-
to-diameter ratio (h/d ) of the specimen was varied from 1.36
to 2.1 .
A schematic diagram of the setup is presented in Fig. 1.
It includes an electric furnace 1 equipped with silicon car-
Refractories and Industrial Ceramics Vol. 47, No. 2, 2006
1083-4877/06/4702-0128 © 2006 Springer Science+Business Media, Inc.
BasNIPIstrom Federal Unitary Enterprise (FUE), Ufa, Russia;
Joint Institute for High Temperatures, Russian Academy of Sci
ences, Moscow, Russia; Birsk State Pedagogical Institute, Birsk,
Fig. 1. Schematic diagram of the experimental setup.