Clear Skies

Amsterdam-based Constellium is a global company with nearly 8,800 employees involved in a variety of industries, including aerospace, automotive and packaging.

The common thread weaving the company’s divisions together is aluminium, which Constellium produces in a variety of what the company calls “aluminium solutions” using several different metallurgical processes.

As a producer of more than 1 million tonnes of aluminium annually at production sites around the world, Constellium pays close attention to how it sources raw materials and how products containing its metals are produced and then recycled.

In the aerospace sector, where metallurgical chemistry is critical, Constellium has developed a closed-loop recycling process that it says benefits the environment while also offering the company a competitive edge.

Flying High
Constellium is a new name on the aluminium scene that was just introduced in 2011. However, the company’s product lines, facilities and many of its people trace back to three legacy companies with deep roots in aluminium: Alcan, AluSuisse and Pechiney.

In May 2011, the now-combined aluminium production activities of these three firms began operating under the Constellium name (excluding Alcan packaging, which had previously spun off as Novelis).

The company’s initial shareholders included mining firm Rio Tinto, the Apollo Global Management Fund and France’s Fonds Stratégique d’Investissement (FSI). Subsequently, Constellium issued public shares on the New York Stock Exchange in 2013.

The company has three primary business units:

• Automotive Structures and Industry, which produces crash management systems and other structural and safety parts as well as extrusions and large profiles for the road and rail transportation, energy and other sectors;
• Packaging and Automotive Rolled Products, which develops, provides and recycles aluminium sheets and coils for packaging applications as well as for heat exchangers and some products for automotive body applications; and
• Aerospace and Transportation, which provides advanced aluminium and specialty materials products for the global aerospace, defense, transportation and industrial sectors. The business unit produces plate, sheet, extrusions and precision casting products for aerospace clients including Airbus, Boeing, Mitsubishi, Spirit, Embraer, Dassault, Bombardier, Kawasaki and others.

Among the initiatives underway within Constellium’s Paris-based Aerospace and Transportation division has been a closed-loop recycling process designed to recover its unique aerospace alloys. The effort is being managed by Bruno Chenal, Constellium’s director for research and development. He has been with Constellium or its predecessor companies (first Pechiney, then Alcan) since 1987.

Three Good Reasons
The production of aircraft and aerospace components is a precision-intensive process that can involve considerable machining and metalworking, resulting in production scrap.

“For some parts, only 10% of the aluminium products delivered by Constellium will actually fly or be part of the aircraft,” says Chenal. “That means as much as 90% of Constellium’s aluminium bought by our aerospace customers will be transformed into chips and offcuts during the manufacturing process.”

Constellium’s best interests are served by recovering this metal for several reasons, he says. By harvesting its own scrap, Constellium knows the chemistry will be right at the foundry or casting plant. “We know that we can make the most of the aluminium [scrap] and its ability to be 100% recycled without losing any of its properties,” says Chenal.

This line of thinking has been critical with the recovery of Constellium’s Airware^® aluminium-lithium material (which the company refers to as a “breakthrough technology”). Airware is designed for all parts of an aerostructure and was developed after considerable research involving nanoscale strengthening. (See the sidebar “Rarefied Air”)

In addition to chemistry, profit-and-loss thinking also figures heavily into making the recycling of specialty aerospace alloys a priority.

“From a recycling perspective, we had to develop a specific process dedicated to this family of advanced [materials],” says Chenal. “With Airware, we are using materials such as lithium and silver, which are very expensive. Finding a way to optimize the cost through recycling is part of the solution that we owe to our customers.”

As well, using a high percentage of internally sourced scrap also provides a hedge “against the variations in the cost of aluminium on global metal markets,” notes Chenal.

The recycling efforts also score well on any sustainability scorecards being maintained. “The energy required to produce recycled aluminium is 20 times lower than that required for primary aluminium,” says Chenal, adding that “one tonne of recycled aluminium saves four tonnes of bauxite.”

He continues, “The more calls for a greener aircraft, the better it is for our aluminium business, for sure. When one considers the major market drivers for the single-aisle civil aviation sector for the coming 20 years and beyond, it is clear that breakthrough solutions will be required to meet the stringent ACARE (Advisory Council for Aeronautics Research in Europe) targets for reduced fuel burn and reduced emissions.”

For Constellium that means a commitment to designing new technologies with specialized chemistries. “In that context, it is believed that airframe weight reductions and improved aerodynamics could contribute to at least 20% of these fuel burn targets, and on weight reduction and aerodynamics aluminium solutions will have a say,” says Chenal.

In the Loop
As explained by Chenal, the aluminium aerospace alloys recycling loop consists of more than one circle and more than one timeline.

In the shorter timeline, Constellium’s aerospace products shipped to manufacturers are generally machined and used within three to six months, generating offcut rates of up to 90%. Working directly with these customers or with scrap company service providers, the goal of the closed-loop system is to fully recover this material stream to recapture the unique chemistry properties that make them ideal feedstock.

The other 10% of Constellium’s products are now part of an airplane or helicopter that will have a useful life of from 30 to 40 years on average.

Although this fraction will follow many different timelines to obsolescence, Constellium is not giving up on the idea of working with aircraft dismantlers to identify Airware and to purchase this scrap for its foundries.

Establishing and managing each of these two loops involves considerable work. “The real challenge is within the management of supply chain, which involves a complex group of players,” says Chenal. “Lead times from demand forecast submitted to aluminium solutions suppliers to the final assembly line at OEMs can take up to 2.5 years,” he adds.

Aircraft orders can be made, cancelled or delayed in spurts, with global exhibitions and economic up-and-down cycles figuring into the timing. As well, it has become increasingly common for aircraft makers or buyers to request design changes in the midst of the production process. “At Constellium, we are working on how to be more predictive and be ready for both the specifications we are aware of and the specifications that could be added along the way,” says Chenal.

The closed-loop efforts fit into what Chenal and other executives at Constellium see as “a holistic approach to aircraft manufacturing.” Thus, says Chenal, “We always bear in mind that we’re selling aluminium solutions for fast-evolving needs. We think that further breakthrough improvement is within reach through the co-optimization of materials, design and fabrication. Our holistic approach is, thus, definitely the right one, and all the more so as it enables us to develop tailored products for our customers.”

Those tailored products with their unique metallurgical properties maintain their intrinsic value as chips and offcuts. “Our products are meant to address all requirements from the supply chain, from design and engineering to manufacturing, maintenance and recycling,” says Chenal.

The author is editor of Recycling Today Global Edition and can be contacted at btaylor@gie.net.