MODIFICATION OF REFRACTORY CERAMIC COMPOSITES
WITH COATINGS BASED ON COMPOUNDS OF TITANIUM
V. A. Doroganov,
V. M. Nartsev,
I. Yu. Moreva,
S. V. Zaitsev,
S. Yu. Kolomytseva,
and E. I. Evtushenko
Translated from Novye Ogneupory, No. 7, pp. 37 – 42, July 2011.
Original article submitted May 31, 2011.
This article describes the properties and features of formation of modifying coatings developed for refractory
materials on the basis of compounds of titanium and zirconium. It also explains the principles behind the inter
action of the resulting composites with melts of metallurgical slag and borosilicate glass.
Keywords: modification, composite coating, magnetron sputtering, contact angle.
Ceramics are used in different areas of industry where
special properties are required. Many of these materials per-
form at the limits of their functional capabilities, so it be-
comes necessary to impart them with additional properties.
This can be done in particular by the application of modify-
ing protective coatings.
The growth of high technology is creating new opportu-
nities for the development of special ceramic composites,
one example being the synthesis of efficient 2D- and
3D-nanostructured composite coatings. The most promising
technologies in this area are vacuum-plasma methods based
on the use of magnetron sputtering . The use of such tech
nologies makes it possible to provide ceramic refractory
products with modifying coatings composed of metals,
non-metals, oxides, nitrides, carbides, or other materials.
Magnetron sputtering also makes it possible to form multi
layer and multiphase structures on the surface of products.
One avenue of research that is very interesting in this re
gard is the study of the surface modification of refractory
materials to decrease their ability to be wetted by aggressive
melts and thus improve their resistance to corrosion.
We used vacuum unit “UniCoat 200” to form modifying
coatings based on titanium and zirconium and their oxides,
nitrides, and carbides. Nitrogen, methane, carbon dioxide,
and oxygen were used as the reaction gases. A mixture of ni
trogen and oxygen was used to apply 3D-composite coatings
based on titanium oxynitrides, while specimens with
2D-composite coatings were obtained by the application of
layers of nitrides and oxides of titanium.
The substrates on which the coatings of titanium and its
compounds were formed were high-alumina refractories syn-
thesized from a highly concentrated ceramic binding suspen-
sion (HCBS) [2, 3] with a mullite-corundum composition.
The density of the HCBS was 2450 kg/m
, its relative mois-
ture content was 13.8%, discharge time was 98 sec, the vol
ume fraction of the solid phase was 0.66, the content of parti
cles larger than 0.63 mm was 2.7 – 2.8%, and the content of
particles smaller than 0.1 mm (100 nm) was 2.6 – 2.7%. The
ceramic substrates were obtained by slip casting. The cast
substrates were in the form of 50 ´ 50 ´ 10 mm tiles and af
ter drying were fired at 1300°C. The shrinkage of the mate
rial from heating was less than 2.0%, open porosity was
16.6 – 16.9%. closed porosity was 0.5%, apparent density
was roughly 2650 kg/m
, and ultimate strength in bending
was at least 35 MPa.
To apply coatings of zirconium and its compounds, tiles
were obtained from an HCBS mixture of high-alumina fire
clay (40 mass %) and a polydisperse filler of similar compo
sition (60 mass %) by the method of semi-dry pressing. The
recommendations in  were followed to make the tiles. Be
fore the coatings were applied, the substrates were carefully
washed to remove contaminants and were then dried to a
constant mass at 150°C. The regimes used for sputtering the
titanium compounds were described in . The parameters
Refractories and Industrial Ceramics Vol. 52, No. 4, November, 2011
1083-4877/11/05204-0272 © 2011 Springer Science+Business Media, Inc.
Belgorod State Technological University, Belgorod, Russia.