Russian Federal Nuclear Center

VNIIEF

K.B. Zhogova, V.N. Piskunov,

G.G. Savkin, V.P.Neznamov

Nanotechnologies and Nanotechnologies and “Tailored” Materials “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.

Nanomaterial manufacturing methods used in the RFNC-VNIIEF:

Mechanical activation, Intensive plastic deformation, Three-dimensional modifying, Plasma and detonation sputtering, Self-propagating synthesisSol-gel method

Nano Objects:Carbon nanostructures (fullerenes; nanotubes; nanofibers);Nanocomposites resulting from mechanical activation of ultra dispersed powders; Nanograin metals obtained by way of intensive deformation; Nanoceramics;Polymer nanocomposites Ultra dispersed powders; Nanolayers and nanocoatings

1. INTRODUCTION

Developed:

“Carbonit”, the material with ultra dispersed structure and enhanced strength and fire resistance

2. FUNDAMENTAL RESULTS AND APPLICATIONS

- 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/kgК,

-  Thermal conductivity less by factor of 2

- Hot pressing temperature

lower by 350 ОСMechanical activator

Micro photo of mechanically activated boron containing composition. The particle size ranges from 120 nm to 1.1 mcm

Developed:

“TUMaN” technical-grade carbon material with nanopores

Performances:Carbon content, % - 96-99.5Open porosity, % - 50-85(as required)Specific surface of open pores, m2/g - up to 600Apparent density, g/cm3 - 0.16-0.8Operational temperature range, оС in the atmosphere - not more than 300 in inert environment - up to 2500Specific electric conductivity, Ohm H cm - 101-105

The material is used to make electron accelerator cathodes. Prospectively, it will be used to produce filtering layers of catalytic stratum substrates.

TUMaN microstructure

TUMaN globule structure

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.

2. FUNDAMENTAL RESULTS AND APPLICATIONS

Obtained: Highly porous nanostructural nickel

The porous nanostructural nickel (PNN) is obtained using the technology of self-propagating 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.

PNN microstructure

Performances: Carbon and oxygen content - tenth fractions of percent Specific surface -8-14 m2/gOpen porosity -85-96 %Apparent porosity -0.356 g/cm3

Compression strength at the porosity of 92% -10-15 N/cm2

(cylinder Ø8mm and height of 8мм)

 Presently, the PNN is used effectively in the devices for working gas purification from admixtures.

2. FUNDAMENTAL RESULTS AND APPLICATIONS

Using the equichannel angular pressing (ECAP) method, volumetric nanostructural materials were obtained.

DiePunch

Blank

ECAP general layout

Refined grain

Numerical simulation of the ECAP process

ECAP die block

The ECAP allows refining of the grains down to 300 nanometers

Copper in the initial state Copper after 8 ECAP cycles

Applications:

• Medicine (stomatology, surgery, orthopedics etc.), • Sporting equipment (trainers, gym apparatus etc.)

2. FUNDAMENTAL RESULTS AND APPLICATIONS

Obtained: Samples of polymer materials with

improved characteristics

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 .

Polymers modified with carbon nanostructures

2. FUNDAMENTAL RESULTS AND APPLICATIONS

Carbon nanostructures

Surface of polymers modified using the МН and PCVD methods

Special gluing equipment

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.

2. FUNDAMENTAL RESULTS AND APPLICATIONS

Numerical simulation methods developed to describe gas diffusion in metals and material destruction

processes under dynamic loadingMolecular 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

3. PREDICTION OF NANOMATERIAL FUNCTIONAL PROPERTIES

Presently, VNIIEF introduces into practice the following advanced theoretical and computational simulation methods:

Density functional method; Molecular dynamics techniques (ab initio and quantum

mechanics); Quantum chemistry methods; 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.

Collective Use Center (CUC) developed for nanomaterial diagnostics

4. PROSPECTS

Activities concentrated on experimental studies of nanomaterial structure and properties

Effective use of purchased costly diagnostic equipment facilitated

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:

4. PROSPECTS

Special educational programs introduced into the learning process

Scientific and educational activities pursued;

Several tutorials issued;

Contacts with research centers of the Academy of Sciences and RosNauka Collective Use Centers established;

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.

CONCLUSION

SAROVSAROV VNIIEFVNIIEF

Thematic International Conference on Bio-, Nano- and Space Technologies