Testing is now being completed on a new titanium alloy that
will lighten aircraft frames. ATI 425 offers reduced weight both through
improved performance and ability to reduce gauge, according to its developer,
Allegheny Technologies Inc. of Pittsburgh.
"Results are better than we anticipated," says Rich
Harshman, chief financial officer of ATI. He adds there is significant
interest in use of the new alloy, which was originally developed for armor
plate on military vehicles. It will be introduced to aerospace markets at the Farnborough
Air Show this July in Hampshire, England.
ATI 425 has a lower forming temperature than the material it
may replace, 6-4 Ti (Ti-6Al-4V), and is being produced in a modern cold-rolling
facility in Louisville, OH.
The newest designs in airframes rely heavily on lightweight
materials such as titanium. The materials' content
of the Boeing Dreamliner 787, for example, is 15 percent titanium. The amount
of titanium used on the Dreamliner increased when titanium fittings were used
the wing attachment to the fuselage in 2008.
ATI has a strategic long-term supply agreement in place with
Boeing, but it's not known if ATI 425 is being used on the Dreamliner.
A key strength of ATI 425 titanium is that it is
comparatively easy to produce and form due to its workability during the
production and forming processes. ATI says duplex annealed ATI 425
titanium plate exhibits good fracture toughness; cold rolled and annealed ATI
425 titanium sheet has been bent to radii of 2.5 times its thickness. The
company reports ATI 425 titanium is also heat treatable and can be
solution-treated and aged to create higher strength levels. The alloy is
Development of specialty alloys such as 425 is part of a
corporate strategy at ATI to move from commoditized metals such as standard
stainless steel to higher value metals, many of which are titanium or nickel
based. In recent years, the company has invested $1.3 billion of internally
generated funds to renew and expand annual titanium sponge production capabilities
to approximately 46 million lbs; expand premium titanium alloy melt and
remelt capacity; expand nickel-based
alloy and superalloy melt and remelt capacity; expand titanium and specialty alloy plate capacity,
and expand premium titanium and nickel-based superalloy forging capacity.
The primary end-market segments for its high-performance
metals are aerospace and defense, the chemical process industry, oil and gas,
electrical energy and medical. There are only four major airframe producers:
Boeing, Airbus S.A.S (an EADS company), Bombardier Aerospace (a division of
Bombardier Inc.) and Embraer (Empresa Brasileira de AeronĂˇutica S.A.).
The primary global producers of nickel-based and other
specialty super alloys are ATI, Carpenter Technology Corp., Special Metals Corp. (a PCC company), Haynes
International and ThyssenKrupp VDM GmbH. The major suppliers of titanium are ATI, Titanium Metals Corp., RMI Titanium (an RTI International Metals
Co.) and VSMPO - AVISMA (Russia). Boeing
has a joint venture agreement
with the Russian supplier to provide components for the Dreamliner.