Constellium bets on lighter, recycled aluminium for future planes

PARIS, June 19 (Reuters) - Constellium CSTM.N is testing lighter alloys and more comprehensive recycling as the aluminium processor positions itself for future single-aisle jets, where competition from composite materials is set to intensify.

Having lost share to composites in larger planes like Airbus' AIR.PA A350 and Boeing's BA.N 787, aluminium suppliers have held their ground in existing smaller models like the Airbus A320, helped by low-density alloys and the industry's familiarity with using aluminium for mass-produced jets.

Aluminium still has plenty of demand to come from current models, after a boom in plane orders and as recent supply chain snags ease. Metals analyst CRU projects 8% average annual growth in aluminium consumption in aerospace in Europe and North America during 2024-29.

But as attention turns to the next generation of narrow-body jets, aluminium will renew its tussle with composites, with suppliers of the metal like Constellium and Novelis HALC.NS competing with composites providers like Hexcel HXL.N.

Planemakers, focused on emissions savings and output rates, are studying novel materials like thermoplastics to ally composites' lightweight appeal with more efficient production processes.

Constellium expects Airbus and Boeing to choose materials for future single-aisle models around 2029-2030, and the supplier aims to push aluminium's edge in recycling as well as further progress in alloys, Philippe Hoffmann, president of aerospace and transportation at Constellium, told Reuters.

"Today, what's on the drawing board or at least on the agenda is the design and concepts for the successor to the A320," Hoffmann said at the Paris Airshow.

In terms of weight, crucial for planemakers, Constellium has demonstrated a weight saving of 20% in tests of a wing concept involving new alloys and a welding process that removes the need for rivets, he said.

The use of friction stir welding, borrowed from Constellium's work on space programmes, will also allow more automation in manufacturing panels, he added.

Constellium sees more room to exploit aluminium's greater reusability compared with composites, with recycled aluminium saving 95% in energy use versus virgin metal.

The firm is studying better retrieval of scrap per alloy during production as well as recovery of metal from a growing fleet of planes at the end of their lifecycle.

"Aluminium was being recycled before we were born," he said. "They (composites) have a lot of qualities but the maturity in recycling is not the same."