Warren
M. Garrison Jr., a professor of materials science and engineering at
Carnegie Mellon University, has developed a new ultra-strength steel of
high fracture toughness that is significantly less expensive to
manufacture than existing products.
The
new steel contains no cobalt and only a relatively small amount of
nickel and therefore is much less expensive than other ultra-high
strength steels of high fracture toughness — all of which contain large
amounts of cobalt and nickel.
Garrison
said the new steel is one of the outcomes of a Small Business
Technology Transfer (STTR) Program, which was funded by the U.S. Navy.
One
of the objectives of the STTR program was the development of an
inexpensive, ultra-strength steel with high fracture toughness that
could be used in Navy aircraft applications. The company in charge of
the STTR program was Navmar Applied Sciences Corporation of Warminster,
Pa., which specializes in engineering and technical support for the
Department of Defense, the U.S. government and private industry.
CMU's
Garrison worked with Jeffrey Waldman, the scientist in charge of the
program at Navmar, and William Frazier, chief scientist at the Air
Vehicle Engineering Department of the Naval Air Systems Command.
The
new steel developed at CMU also has excellent resistance to crack
growth during stress corrosion cracking in salt water. "The rate of
crack growth during stress corrosion cracking of the new steel is
comparable to that of other ultra-high strength steels of high fracture
toughness and is much better than that of low alloy steel 300M, which is
the steel used in the landing gear of most commercial aircraft," said
Garrison, who has a patent pending for the new steel.
The
researchers report that the next step in the development of the new
steel would be to assess its properties in commercial scale heats. While
the alloy was developed with Navy aircraft applications in mind, given
its low cost and high toughness, it could be used for other
applications.
Carnegie Mellon is a private, internationally ranked
research university with programs in areas ranging from science,
technology and business, to public policy, the humanities and the arts.
More than 12,000 students in the university's seven schools and colleges
benefit from a small student-to-faculty ratio and an education
characterized by its focus on creating and implementing solutions for
real problems, interdisciplinary collaboration and innovation. A global
university, Carnegie Mellon's main campus in the United States is in
Pittsburgh, Pa. It has campuses in California's Silicon Valley and
Qatar, and programs in Africa, Asia, Australia, Europe and Mexico. The
university has exceeded its $1 billion campaign titled "Inspire
Innovation: The Campaign for Carnegie Mellon University," which aims to
build its endowment, support faculty, students and innovative research,
and enhance the physical campus with equipment and facility
improvements. The 30 campaign closes 2013.
