HIGHLY RESISTANT DISPENSING NOZZLES BASED ON ZIRCONIUM
DIOXIDE FOR PROFILED CBCM. PART 1. STRUCTURE
AND PHYSICOMECHANICAL PROPERTIES OF MATERIALS BASED
ON ZIRCONIUM DIOXIDE FOR PRODUCING CBCM DISPENSING NOZZLES
L. M. Aksel’rod,
V. I. Rumyantsev,
N. Yu. Korableva,
N. V. Belykh,
and Ya. G. Dyatlova
Translated from Novye Ogneupory, No. 3, pp. 127 – 131, March 2008.
Original article submitted December 25, 2007.
Technology is developed for preparing refractory components made of partially stabilized zirconium dioxide
using an isostatic compaction press. Technology is provided for manufacturing dispensing nozzles using
combined and separately stabilized zirconium dioxide, and also indices of the refractories obtained and
imported materials are compared.
Extensive introduction of continuous pouring of steel in
metallurgical production has promoted progress in refractory
material technology. An important element of a tapping unit
for intermediate ladles of CBCM is the dispensing nozzle.
An increase in the frequency of pouring and expansion of the
grades of poured metal requires production of refractory
materials for dispensing nozzles distinguished by high metal
and slag resistance and thermomechanical stability. Use of
these dispensing nozzles makes it possible to reduce the
specific consumption of refractory materials per ton of steel,
to increase CBCM productivity, and to increase the quality of
a cast steel billet.
Among materials used extensively for manufacturing
high resistance refractory articles, this relates primarily to
zirconium dioxide [1 – 6]. In fact dispensing nozzles made of
zirconium dioxide, partly stabilized with magnesium oxide
(PSZD), have high mechanical strength and metal and slag
resistance, and they make it possible to pour steel over tens
of hours. In spite of the fact that appropriate research was
carried out quite a long time ago, they have not found
extensive use in the practice of the Russian refractory
industry, apparently as a result of the comparatively high cots
of this refractory. However, the increase in production
(number of melts, poured constantly through one inter
mediate ladle) and expansion of the grades of metal poured
in CBCM has given rise to the profitability of using zirco-
nium dioxide as a refractory metal conduit . Currently in
the world market, including Russia, components made of
PSZD are also supplied such well-known firms as Vesuvius
(Belgium, Great Britain), RHI AG (Austria), and Pohl
In this article information is provided about development
of materials based on domestic raw materials suitable for
manufacturing dispensing nozzles operating intermediate
CBCM ladles and they are compared with the technical and
economic operating characteristics of imported analogs.
Proceeding from service conditions, the material for
dispensing nozzles should relate to a dense material distin
guished by high mechanical strength, wear resistance, heat
resistance and phase stability. Technology developed for
manufacturing these components has been developed with
the following indices: weight faction of ZrO
not less than
94%, apparent density more than 4.84 g/cm
, open porosity
not more than 10%, ultimate strength in compression not less
than 180 MPa.
STARTING MATERIALS AND STUDY PROCEDURE
Domestic raw material was used in order to prepare
charges, i.e. baddeleyite concentrate from the Kovdorsk
GOK in the form of powder grade KP-B and KP-S (TU
2360-001-598980250003) with a content of (ZrO
not less than 99.3%. Magnesium oxide (GOST 45236) was
used as a stabilizer. In order to reduce the sintering
Refractories and Industrial Ceramics Vol. 49, No. 2, 2008
1083-4877/08/4902-0116 © 2008 Springer Science+Business Media, Inc.
OOO Gruppa Magneizt, OOO VIRIAL, Russia.