NASA’s Friction-Stir Welded, Spun-Formed Tank Dome Debuts With Alcoa Aluminum Lithium

March 30, 2010

DAVENPORT, Iowa–Alcoa (NYSE:AA) announced that its aluminum lithium plate is featured in
NASA’s friction-stir welded, spun-form dome that makes its debut today
at the Marshall Space Flight Center in Huntsville, Ala. Along with
Lockheed Martin and MT Aerospace, Alcoa engineers were part of the
consulting team providing materials expertise that helped to develop
this groundbreaking technology – the first full-scale friction-stir
welded and spun-formed tank dome designed for use in large liquid
propellant tanks.

“We want to congratulate NASA on this important achievement,” said Harry
Kiskaddon, global commercial director, Alcoa Rolled Products. “The tank
dome proves the viability of using friction-stir welding to reliably and
cost-effectively join large aluminum-lithium plates for high-strength
applications. It is a great first step in testing the fundamentals of
this technology – and a terrific example of how next-generation aluminum
alloys continue to push the boundaries of innovation. It illustrates how
Alcoa delivers both products and technology innovations to designers to
enable more efficient and high-performance structures.”

The 18-foot dome was developed with friction-stir welding, a welding
process specifically designed for working with aluminum, and spin
forming, a metal-working process used to form round, symmetric parts.
Through this new technology, NASA hopes to reduce the weight of future
large liquid propellant tanks by 25 percent. Additionally, the cost of
producing the tanks is reduced because friction-stir welding and the
concave net shape spin forming process eliminate manufacturing steps,
such as machining.

“We were able to supply the aluminum-lithium plates needed for the dome
because our Davenport, Iowa, facility is the widest hot rolling mill in
the world,” said Kiskaddon. “Two of our wide plates were joined into one
plate using the friction-stir weld process.”

Since its inception, the space program has used Alcoa aluminum. Alcoa’s
Davenport Works is the only supplier certified by NASA to provide the
light-gauge, high-quality, aluminum-lithium plate for crew launch
vehicles.

NASA awarded Alcoa contracts now totaling $18.7 million since 2007 to
develop manufacturing capabilities and to supply the initial
requirements for aluminum-lithium alloy products. A year later, NASA
certified Alcoa as the sole supplier of the high performance
aluminum-lithium alloy thin plate. In supplying plate products to NASA
since 2008, Alcoa’s Technical Center and Davenport Works facilities have
demonstrated the product capability, manufacturing flexibility and
technological innovation needed for NASA to meet its program goals.

Alcoa is a leader in the development of aluminum-lithium alloys, which
are lightweight, low density and strong. Aluminum-lithium alloy 2099 won
the R&D 100 Award, considered the Oscars of Invention, in 2007.

About Alcoa

Alcoa is the world’s leading producer of primary aluminum, fabricated
aluminum and alumina. In addition to inventing the modern-day aluminum
industry, Alcoa innovation has been behind major milestones in the
aerospace, automotive, packaging, building and construction, commercial
transportation, consumer electronics and industrial markets over the
past 120 years. Among the solutions Alcoa markets are flat-rolled
products, hard alloy extrusions, and forgings, as well as Alcoa® wheels,
fastening systems, precision and investment castings, and building
systems in addition to its expertise in other light metals such as
titanium and nickel-based super alloys. Sustainability is an integral
part of Alcoa’s operating practices and the product design and
engineering it provides to customers. Alcoa has been a member of the Dow
Jones Sustainability Index for eight consecutive years and approximately
75 percent of all of the aluminum ever produced since 1888 is still in
active use today. Alcoa employs approximately 59,000 people in 31
countries across the world. More information can be found at www.alcoa.com.