K.B. Zhogova, V.N. Piskunov, G.G. Savkin, V.P.NeznamovNanotechnologies 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 decadeVNIIEF 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 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 Nanomaterial manufacturing methods used in the RFNC-VNIIEF: • Mechanical activation, • Intensive plastic deformation, • Three-dimensional modifying, • Plasma and detonation sputtering, • Self-propagating synthesis • Sol-gel method
2. FUNDAMENTAL RESULTS AND APPLICATIONS Developed: “Carbonit”, the material with ultra dispersed structure and enhanced strength and fire resistance -Average density of internal elementshigherby 13%; higher edge density; - Higher failure stress: by factor of 4in compression, and by factor of 1.8 in bending; - Impact ductilityHigher byfactor of 1.3; - Higher heat capacity, i.e. up to 870 J/kgК, - Thermal conductivity less by factor of2 - Hot pressing temperature lower by 350 ОС Micro photo of mechanically activated boron containing composition. The particle size ranges from 120 nm to 1.1 mcm Mechanical activator
2. FUNDAMENTAL RESULTS AND APPLICATIONS 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. Developed: “TUMaN” technical-grade carbon material with nanopores Performances: Carbon content, %- 96-99.5 Open porosity, % - 50-85(as required) Specific surface of open pores, m2/g- up to 600 Apparent density, g/cm3- 0.16-0.8 Operational temperature range,оС in the atmosphere - not more than 300 in inert environment - up to 2500 Specific 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 globule structure TUMaN microstructure
2. FUNDAMENTAL RESULTS AND APPLICATIONS 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 75nm. Obtained: Highly porous nanostructural nickel 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 Ø8mm and height of 8мм) Presently, the PNN is used effectively in the devices for working gas purification from admixtures. PNN microstructure
2. FUNDAMENTAL RESULTS AND APPLICATIONS Die The ECAPallows refining of the grains down to 300 nanometers Punch ECAP general layout Refined grain Copper in the initial state Copper after 8 ECAP cycles Numerical simulation of the ECAP process Blank ECAP die block Using the equichannel angular pressing (ECAP) method, volumetric nanostructural materials were obtained. • 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 Polymers modified with carbon nanostructures Surface of polymers modified using the МН 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: • Density functional method; • Molecular dynamics techniques (ab initio and quantum mechanics); • Quantum chemistry methods; • Multilayer simulation (combination ofphysical elements methods and cluster dynamics). • Relying onthetheoretical 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: • Scientific and educational activities pursued; • Several tutorials issued; • Contacts with research centers of the Academy of Sciences and RosNauka Collective Use Centers established; • Special educational programsintroduced intothe 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.
SAROVVNIIEF Thematic International Conference on Bio-, Nano- and Space Technologies