K. Maevskii

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CUMULATIVE SYNTHESIS OF
SUPERHARD COATINGS
S.A. Kinelovskii1,4, S.A. Gromilov 2,4, M.A. Korchagin3,
Yu.N. Popov4, and K.K. Maevskii1
1- Lavrent'ev Institute of Hydrodynamics of Russian Academy of Sciences;
2 - Nikolaev Institute of Inorganic Chemistry of Russian Academy of Sciences;
3- Institute for Solid State Chemistry and Mechanochemistry of Russian Academy of Sciences;
4 - Novosibirsk State University
e-mail: konstantinm@hydro.nsc.ru
EPNM–2012
May 2–5, 2012, Strasbourg, France
This work was supported by the Russian Foundation for Basic Research (project No. 10-03-00527)
CUMULATIVE SYNTHESIS or SHAPED CHARGE SYNTHESIS
2
Area of the forming of cubic phase β-WC on the
plane of phase States of tungsten-carbon.
Area of the forming of cubic phases of TiC on
the plane of phase States of titanium-carbon.
S. A. Kinelovskii, K. K. Maevskii “Simple Model for Calculating Shock Adiabats of Powder Mixtures”
Combustion, Explosion, and Shock Waves, Vol. 47, No. 6, 2011
3
Grinding surface on steel using mixture of WSibunit-Co
Sample construction staging area between the surface
and the unperturbed steel matrix
(W + 1,1 C) + 20 %(wt.)Co
mechanically activated composites
30% (wt.) (WC + 30%(wt.)TiC)/70%(wt.) (Ni + Cr)
4
For the mixture W + C + Co micro hardness of surface layer Hv = 13 – 20 GPa for a
single evaporation on steel target.
For the composition WC+ TiC +(Ni-Cr) micro hardness of surface layer Hv = 10 – 22 GPa
for a single evaporation on to steel target. (pure steel – HV = 1,1 GPa). Cover fixed cubic
phase based on chromium (Cr), absent in the original mixture.
1
2
The use of mechanically activated
30% (wt.) (WC +
30%(wt.)TiC)/70%(wt.) (Ni + Cr)
composites for cumulative deposition
onto titanium substrate automatically
resulted in formation of a functionally
graded coating in which the nearsurface layer was TiC-rich while the
inner layers, WB-rich.
5
Consider the following case where new phases are formed in contact with the surface
of the particle flux cumulative targets.
When the cumulative particle flux with metal obstacle on the surface of obstacle may to
form a kind of layer - covering. On the one hand, this layer can contain any phase
synthesized under collapsing shape charge. On the other hand, the interaction of
particles with the material obstacle possible synthesis of new phases and then coating is
integrated in the crystal lattice. In this case, one may speak of cumulative synthesis.
6
Carbon (C) + ammonium nitrate (NH4NO3) in titanium target,  = 45
(111) c
(200) c
(101) g
(100) g
Intensity
(002) g
2θ, degree
7
Measuring micro hardness
For lining of mixture B–NH4NO3 mixture (1 : 2 by volume, α = 200 ) the average surfaces
microhardness equals 18GPa and maximum value = 39.55 GPa (from here onwards, the load 200 g)
when you go to the triple interaction of these values were 39.0, respectively, and 44.5 GPa. For
mixtures of graphite + NH4NO3 transition to three-fold interaction has led to an average micro hardness
29.5 GPa, maximum 35.4 GPa.
In the search for other mixed trains to shaped charge lining, graphite was replaced by sibunit. -Use a
mixture of sibunit + NH4NO3 (1 : 2 by volume) has the average value of micro hardness layer 41.2 GPa
at maximum height 41.9 GPa, suggesting a high degree of homogeneity of formed high solid layer.
8
Decomposition of precursor shaped charge currents
and the synthesis of new compounds
mixture of powders
(TiB2+B4C+(Ti +2B)+W)

TiB2, β-WB, W2B, W
Intensity
β-WB
TiB2
β-WB
TiB2
Inset shows changing of diffraction
pattern after grinding samples
2θ, degree
Roentgen-phase analysis showed the presence of four crystalline phases
in terms of elementary cells (EC) close to the TiB2, β-WB, W2B, W.
9
Decomposition of precursor shaped charge currents
and the synthesis of new compounds
I, int./c
mixture of powders
(TiB2+B4C+W)

TiB2, β-WB, W2B, W
I, int./c
2θ, degree
At the top curve insert shows
the classification of
fundamental diffraction lines
detected phases, on the bottom
curve - depth-variation of
phase-change.
2θ, degree
Analysis of the results shows that are used with collapsing lining pressure and temperature in this case is
insufficient to break the compound TiB2 – practically all of diboride titanium saved. Phase B4C all
decays and freed boron forms two phases of boride of tungsten.
10
Estimation of pressure and temperature to be used in shaped charge currents
for some mixtures
P, Gpa
In these experiments, received coverage on titanium, micro hardness (Hv = 42 Hpa) is
significantly higher than the micro hardness phases of the borides of titanium and tungsten
11
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