Keblinski Receives Prestigious NSF Award
Troy, N.Y. — Pawel Keblinski has been awarded a five-year,
$300,000 Faculty Early Career Development (CAREER) Award from
the National Science Foundation. The CAREER Award is the NSF’s
most prestigious honor for faculty members who are at the
beginning of their academic careers.
Keblinski, assistant professor of materials science and
engineering at Rensselaer Polytechnic Institute, is the third
Rensselaer faculty member this year and the 15th in the last
three years to be recognized with a CAREER Award. He joined the
Rensselaer faculty in 1999.
Keblinski is studying the role of interfaces on mechanical
properties of polycrystals, such as diamond thin films grown by
chemical deposition. His research in modeling the atomic
bonding and the mechanical properties of polycrystalline
diamonds will lead to better design of nanoscale materials that
are stronger and less brittle.
While gem diamonds are single-crystal, diamond thin films
grown by chemical deposition methods are polycrystal, which
means they consist of many small crystalline diamond grains
separated by interfaces, or edges, says Keblinski, a research
leader of Rensselaer’s nanotechnology modeling team. The
strength of bonds between atoms at these interfaces is
generally weaker than in perfect diamond crystals, which causes
the material to be more brittle.
The role of interfaces becomes more significant at the
nanoscale level because smaller crystals mean more interfaces,
which could lead to even weaker material. Remarkably,
experiments demonstrated that the strength of nanocrystalline
diamond is essentially the same as that of gem diamond, which
Keblinski explained with his modeling. Brittle materials fail
because cracks grow and spread in a specific direction. But a
crack that forms in one crystal could be stopped by an
interface with enough strength and a different orientation of
the crystal on the other side of the interface.
“Understanding the role of interfaces on mechanical
properties, such as hardness and durability, is essential to
designing materials,” said Keblinski. “Because polycrystals are
far more common in nature than single crystals, the knowledge
derived from our studies of polycrystalline diamond can apply
to other brittle materials such as ceramics.” Ceramics are
necessary for hard coatings or thermal protection barriers in
turbines, for example.
Contact: Patricia Azriel
Phone: (518) 276-6531