PREPARATION METHODS FOR COMPOSITE CERAMIC MATERIALS
BASED ON AlN–BN (REVIEW)
R. Yu. Kuftyrev,
A. V. Belyakov,
and I. G. Kuznetsova
Translated from Novye Ogneupory, No. 4, pp. 65 – 73, April, 2013.
Original article submitted February 12, 2013.
The main methods are considered for preparing composite ceramic material based on AlN and BN com
pounds, combining component properties successfully: high thermal conductivity and good mechanical prop
erties of aluminum nitride supplemented by high dielectric properties and easy workability of boron nitride.
Methods are provided for preparing ceramics from powder mixtures, i.e., normal sintering, hot pressing, reac
tion sintering, sintering in a spark discharge (SPS), and also methods making it possible to prepare material
with a more homogeneous structure using organic and inorganic precursors.
Keywords: composite material, aluminum nitride, boron nitride.
Ceramics based on hexagonal boron nitride exhibit high
electrical insulation properties, thermal shock resistance,
chemical resistance, strength at high temperature, high ther-
mal conductivity, stability in a vacuum, considerable thermal
neutron capture cross section, combined with good
machinability, and good refractory properties. Aluminum
nitride ceramics also exhibit high physicotechnical property
indices, such as thermal conductivity, electrical resistance,
refractoriness, thermal shock resistance, and resistance to
corrosive chemical media, i.e., molten metals and alloys .
Currently several companies offer ceramics based on the
AlN–BN system. Material properties are provided in Table 1,
from which it is seen that an AlN–BN composite exhibits a
collection of unique properties, i.e., high thermal conductiv
ity, high electrical resistance, good dielectric properties, and
good mechanical properties. Producers claim material high
corrosion resistance and good machinability. This combina
tion of properties makes it possible to use this composite ma
terial in various areas of industry: in electronic technology
for components requiring output of a considerable amount of
heat, and having high electrical resistance; in power elec
tronic component requiring high dielectric properties at
ultrahigh frequencies (low value of dielectric constant and
dielectric losses); in radio electronics for obtaining radiopar
ent components; in vacuum technology for creating various
refractory objects and crucibles for vacuum deposition; in in
strument building for creating heat dissipaters, insulators,
and protective tubes for special furnaces, components, and
refractory objects with low linear thermal expansion coeffi-
cient (LTEC); in other areas as a structural material. In addi-
tion, due to good machinability of this composite there is a
possibility of creating components of complex shape based
upon it with a high degree of accuracy, which is very impor-
tant in electronics.
Attempts to create materials based on BN and AlN,
which combine the favorable effects of the components, have
been undertaken for quite a long time. In the USSR work was
carried out under the leadership of Prof. Samsonov. In a dis
sertation Prikhodko presented results of studying conditions
for preparing dense objects of AlN and BN by various meth
ods . Samsonov and Kusalapova have presented methods
for preparation and some properties AlN–BN system materi
als in books [6, 7].
We have reviewed articles published in the last decade
devoted to preparing materials of the AlN–BN system. Mate
rials based on AlN–BN are prepared by all the main methods
of ceramic technology: normal sintering, hot compaction,
and reaction sintering. A mixture of starting components is
prepared both by traditional methods in a ball mill, and also
by various chemical methods.
SINTERING WITHOUT APPLICATION
OF EXTERNAL PRESSURE
The authors of  carried out research for the effect of
adding BN up to 10 wt.% on the main mechanical and
Refractories and Industrial Ceramics Vol. 54, No. 2, July, 2013
1083-4877/13/05402-0141 © 2013 Springer Science+Business Media New York
FGBOU VPO D. I. Mendeleev Russian Chemical-Technological
University, Moscow, Russia.