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NanoMat 2018 Nano Research & Applications
ISSN: 2471-9838 Page 50
April 26-27, 2018
Rome, Italy
17th Edition of International Conference on
Emerging Trends in
Materials Science and
Nanotechnology
Superhard materials are widely employed in industry for
production of cutting and polishing tools, as well as anti-
abrasive coatings. The synthesis of man-made superhard phases
started from the early 1950s, as soon as the development of high-
pressure techniques allowed reaching the pressures necessary
for diamond synthesis. However, the experimental and theoretical
design of novel superhardmaterials still remains a great challenge
to materials scientists. To this aim, experimental observations
and simulations suggest that for many polycrystalline materials
there is an optimal grain size (usually in the range of dozens of
nanometers) which results in a significant, up to 50-70%, increase
of hardness of the material in comparison with that of its coarse
grain counterpart. This increase in hardness is known as the Hall–
Petch effect. That’s why the synthesis of bulk nanostructured
materials remains the least-explored but challenging domain that
allows combination of desired physical, chemical, andmechanical
properties and gives rise to nanoelectronics, nanomechanics,
band gap engineering, etc. Boron-based materials comprise
many covalent diamond-like and boron-rich compounds
whose structures are three-dimensional nets of short and
strong covalent bonds responsible for their extreme hardness.
In this talk, I will show that the use of very high pressures and
temperatures combined with the in situ probe by x-ray diffraction
with synchrotron radiation is the methodological key to control
the composition and microstructure of new bulk nanostructured
and superhard boron compounds and I will give many examples
from our recent studies, leading to patent some new strategic
compounds.
Recent Publications
1. J P Itié, E Girard, N Guignot, Y Le Godec and MMezouar
(2015) Crystallography under high pressure using
synchrotron radiation, Journal of Physics D: Applied
Physics 48, 504007.
Biography
Yann Le Godec is a CNRS Researcher and experienced user of large-scale
instruments (ESRF, SOLEIL, DESY, DIAMOND, ILL, ISIS, etc.) for high pres-
sure research. During last years, he has used high pressure to create new
solids with advanced mechanical and physical properties. His activities led
him to patent numerous new dense materials with light elements that have
aroused considerable interest in search for novel superhard phases all over
the world. He has been also leading in the development of in situ high pres-
sure - high temperature diffraction techniques, both for x-rays and neutron
studies. For his work, he has received the CNRS “Medaille de Bronze” Award.
High pressure synthesis of new superhard nanostructured
boron compounds
Yann Le Godec
IMPMC, CNRS - Sorbonne Université, France
Yann Le Godec, Nano Res Appl, Volume:4
DOI: 10.21767/2471-9838-C1-008