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Russian Federal Nuclear Center
VNIIEF
K.B. Zhogova, V.N. Piskunov,
G.G. Savkin, V.P.Neznamov
Nanotechnologies and
“Tailored” Materials
RFNC-VNIIEF fundamental results in
nanomaterials and nanotechnologies
Thematic International Conference on Bio-, Nano- and Space Technologies
1. INTRODUCTION
Development of materials with predetermined
properties (i.e. “tailored” materials) is one of the
key nanotechnology areas that may bring positive
effects in the nearest perspective.
For the recent decade VNIIEF has been
pursuing the R&D(s) in nanomaterials.
Primarily, the efforts are focused on the
functional
characteristics
upgrade
of
consolidated
nanomaterials,
i.e.:
metals,
ceramics, polymers and coatings.
1. INTRODUCTION
Nanomaterial manufacturing methods
used in the RFNC-VNIIEF:
пѓјMechanical activation,
пѓјIntensive plastic deformation,
пѓјThree-dimensional modifying,
пѓјPlasma and detonation sputtering,
пѓјSelf-propagating synthesis
пѓјSol-gel method
Nano Objects:
пѓјCarbon nanostructures (fullerenes;
nanotubes; nanofibers);
пѓјNanocomposites resulting from
mechanical activation of ultra dispersed
powders;
пѓјNanograin metals obtained by way of
intensive deformation;
пѓјNanoceramics;
пѓјPolymer nanocomposites
пѓјUltra dispersed powders;
пѓјNanolayers and nanocoatings
2. FUNDAMENTAL RESULTS AND APPLICATIONS
Developed:
“Carbonit”, the material with ultra dispersed structure and
enhanced strength and fire resistance
Micro photo of mechanically
activated boron containing
composition. The particle size
ranges from 120 nm to 1.1 mcm
Mechanical activator
- Average density of internal
elements higher by 13%; higher
edge density;
- Higher failure stress: by factor of
4 in compression, and by factor of
1.8 in bending;
- Impact ductility Higher by factor
of 1.3;
- Higher heat capacity, i.e. up to
870 J/kgРљ,
- Thermal conductivity less by
factor of 2
- Hot pressing temperature
lower by 350 РћРЎ
2. FUNDAMENTAL RESULTS AND APPLICATIONS
Developed:
“TUMaN” technical-grade carbon material with nanopores
TUMaN is a structural glass carbon open-pore material comprised by 2-10 mcm globules,
which in their consist of chaotic 2 nm nano blocks separated with 1.5-2 nm pores.
The manufacturing technology is carbonization of the polymer precursor obtained using the
sol-gel technology.
Performances:
Carbon content, %
Open porosity, %
Specific surface of open pores, m2/g
Apparent density, g/cm3
Operational temperature range, РѕРЎ
in the atmosphere
in inert environment
Specific electric conductivity, Ohm H cm
- 96-99.5
- 50-85(as required)
- up to 600
- 0.16-0.8
- not more than 300
- up to 2500
- 101-105
TUMaN globule structure
TUMaN microstructure
The material is used to make electron accelerator
cathodes. Prospectively, it will be used to
produce filtering layers of catalytic stratum
substrates.
2. FUNDAMENTAL RESULTS AND APPLICATIONS
Obtained: Highly porous nanostructural nickel
The porous nanostructural nickel (PNN) is obtained using the technology of selfpropagating high-temperature synthesis (SHS).
The PNN is a highly porous material with the structure of interlaced loosely packed porous
films. Each film has a nano crystalline structure with the average crystallite size of 75 nm.
Performances:
Carbon and oxygen content
- tenth fractions of percent
Specific surface
-8-14 m2/g
Open porosity
-85-96 %
Apparent porosity
-0.356 g/cm3
Compression strength at the porosity of 92%
-10-15 N/cm2
(cylinder Г�8mm and height of 8РјРј)
Presently, the PNN is used effectively in the devices for
working gas purification from admixtures.
PNN microstructure
2. FUNDAMENTAL RESULTS AND APPLICATIONS
Using the equichannel angular pressing (ECAP) method,
volumetric nanostructural materials were obtained.
The ECAP allows refining of the grains down to 300
nanometers
Refined grain
Numerical simulation of the ECAP process
Copper in the initial state
Punch
Copper after 8 ECAP cycles
Die
Applications:
• Medicine (stomatology, surgery,
orthopedics etc.),
• Sporting equipment (trainers, gym
apparatus etc.)
Blank
ECAP general layout
ECAP die block
2. FUNDAMENTAL RESULTS AND APPLICATIONS
Obtained: Samples of polymer materials with
improved characteristics
Polymers modified with carbon nanostructures
Surface of polymers modified
using the РњРќ and PCVD
methods
Special gluing equipment
Carbon nanostructures
The modification allowed us to improve significantly thermal and mechanical properties of the polymers, as well as their
radiation resistance:
•Destruction initiation temperature increased by 30-60 оС,
•Destruction rate decreased by factor of 2-4,
•Rupture relative elongation increased by factor of 4.5,
•Polymer coating plasticity enhanced,
•Cracking reduced in operation, while preserving the rupture strength and vapor permeability .
2. FUNDAMENTAL RESULTS AND APPLICATIONS
Technologies to obtain protective coatings using
plasma and detonation sputtering of ultra
dispersed materials developed
Using detonation sputtering, nanocoatings
obtained from mechanically activated
gadolinium oxide powder, as well as
nanostructural
titanium/aluminum
coatings, and aluminum coatings from
ultra dispersed aluminum powder.
The coating adhesion strength and density
improved. The adhesion strength proved
to be 2 times as high as the standard one.
Photo of copper disks with the nanostructural
titanium/aluminum coatings with the thickness
of 10 nm and 50 nm.
3. PREDICTION OF NANOMATERIAL FUNCTIONAL
PROPERTIES
Numerical simulation methods developed to describe
gas diffusion in metals and material destruction
processes under dynamic loading
Molecular dynamics codes were used in the calculations. These techniques are
used to compute the behavior of hydrogen and its isotopes in structural
materials; describe mechanical properties of nanostructural metals; and simulate
nanomaterial manufacturing technologies and functional properties.
Potential energy surface for hydrogen atoms in
palladium interstitial sites
The model for construction of metal polycrystalline grain
structure
3. PREDICTION OF NANOMATERIAL FUNCTIONAL
PROPERTIES
Presently, VNIIEF introduces into practice the following
advanced theoretical and computational simulation methods:
пѓ� Density functional method;
пѓ� Molecular dynamics techniques (ab initio and quantum
mechanics);
пѓ� Quantum chemistry methods;
пѓ� Multilayer simulation (combination of physical elements
methods and cluster dynamics).
Relying on the theoretical and computational simulation
methods, it is planned to predict functional properties of
nanomaterials and define their potential applications in different
engineered structures.
4. PROSPECTS
Collective Use Center (CUC) developed for nanomaterial
diagnostics
 Activities concentrated on experimental
studies of nanomaterial structure and
properties
Effective use of
purchased costly
diagnostic
equipment
facilitated
4. PROSPECTS
In 2002 “Disperse Systems and Nanomaterials” research
laboratory was founded in Sarov Engineering Physics Institute
with the assistance of the RFNC-VNIIEF and RF Ministry of
Science:
пѓ� Scientific and educational activities pursued;
пѓ�Several tutorials issued;
пѓ�Contacts with research centers of the Academy of Sciences and
RosNauka Collective Use Centers established;
пѓ�Special educational programs introduced
into the learning process
CONCLUSION
Assimilation and launching of new technologies
requires a joint, interindustry (end even international)
approach.
The RFNC-VNIIEF is a part of “The Center of
RosAtom for Nanotechnologies and Nanomaterials” and
has close links with the regional center “Nanoindustry”
and affiliations of RoasAtom concern.
We are positive that a highs scientific and
technical potential available in the RFNC-VNIIEF and
good working relationships with the other organizations
will serve as the basis for actual investments, which
should convert nanoscince into nanoindustry.
SAROV
VNIIEF
Thematic International Conference on Bio-, Nano- and Space Technologies
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