CERAMIC FILMS: HYDRODYNAMIC
AND TOPOCHEMICAL MEMORY EFFECTS
I. L. Trubnikov
and A. A. Zubkov
Translated from Novye Ogneupory, No. 7, pp. 47 – 58, July, 2007.
Original article submitted January 19, 2007.
The effect of self-organization is identified in the production of ceramic films on different bases using the so
lution technology. The reasons for the emergence of this effect are discussed and a thermocapillary mecha
nism for the origin of dissipative structures is proposed. Topochemical processes occurring in thermolysis of
abietates are considered. The prospects of the synergetic approach to solving topical problems of film mate
rials are demonstrated.
Films of thickness ranging from a few nanometers to
submicrons formed on various solid materials are exten-
sively applied in different spheres. They play a significant
role in theoretical studies dedicated to physical chemistry of
surface , thermodynamics of small-size structures [2, 3],
and science of materials . The main aim of the science of
film materials is obtaining modified materials  and hetero-
structures [6, 7] with a wide set of properties (electrophysical
[8 – 10], optical , mechanical, etc.) and the development
of technological methods for synthesizing film systems with
preset properties [12 – 14].
The surface of refractories in thermal plants experience
the effect of gaseous and liquid corrodients; as a conse
quence, their surface layers undergo spontaneous uncont
rolled modification, which abruptly alters various parameters
of critical structural units. Therefore, a thorough identifica
tion of these processes and development of methods for in
hibiting these processes are urgent challenges as well.
Evidently, a sufficiently thin film is a particular state of a
condensed material, which differs significantly from the
structure and properties of its solid analogs. It is also evident
that the physicochemical properties of a film to a great extent
depend on its surface state, stoichiometry, crystallinity, den
sity, microstructure, and crystalline orientation, which in its
turn depend to a large extent on the methods for producing
Contemporary research methods  convincingly de
monstrate that the surface of even the most perfect single
crystals is highly heterogeneous in its structural, electric, and
chemical properties. Obviously the surface of ceramics is
even more variable. In the transition to small-size structures,
especially those containing nanostructures as their compo-
nents or fragments, the situation becomes even more compli-
cated. Here the number of atoms in the surface layer (the
so-called s-phase) becomes commensurate with the number
of atoms in the remaining volume (the V-phase). In this case
the known characteristic properties of the V-phase become
significantly altered. These changes are called the dimen-
sional effects. Structural effects are manifested in a percepti
ble variation of interatom distances, distortion and rearrange
ment of the elementary cell, and even in amorphizing, i.e.,
the loss of the long-range order in the atom environment.
Chemical effects, as a rule, modify the stoichiometric com
position of the material. Certain dimensional physical effects
are especially clearly manifested: changes of melting tempera
tures or jumps in electrophysical and mechanical properties.
As early as 1939 Folmer established that as a particle
size decreases, the effect of the surface on the volume grows.
Thus, for a small spherical particle of a radius r, the melting
decreases due to the increased vapor pressure
above the convex curved surface:
= T exp(2sV
where T is the melting temperature of the “solid” material; s
is the specific surface energy of the interface; V
is the molar
volume of the solid phase; Q is the molar melting enthalpy.
This dependence is due to the fact that under a small cur
vature radius a substantial number of atoms are localized on
the surface with a fewer number of neighbors than in the vo
Refractories and Industrial Ceramics Vol. 48, No. 3, 2007
1083-4877/07/4803-0208 © 2007 Springer Science+Business Media, Inc.
South Federal University (Rostov State University), Russia.