New process can help ‘make aircraft recycling a reality’

Australia – Researchers at Australia’s Deakin University have developed a technology ‘that should open the way to recycling the bulk of the 200 000 aircraft currently traversing the airways’. The university calculates this breakthrough would see around 6 million tonnes and billions of dollars’ worth of high-performance aluminium alloys retained within the airline industry.

Dr Thomas Dorin and his co-workers have built a prototype of the recycling process at Deakin’s Institute for Frontier Materials at Waurn Ponds. Said to deliver ‘an enhancement of the alloys’ performances’, Dorin says of the process: ‘We adapted the steel Direct Strip Casting technology, which uses a vertical twin copper roll system to process the alloys.’

The key was using copper instead of steel roller to achieve extremely high cooling rates of up to 10 000 degC per second. ‘The great thermal conductivity of copper achieves the rapid solidification needed to refine the alloy impurities,’ adds the metallurgist, who was formerly with aluminium alloy giant Constellium.

The technology could lead to the annual recycling of around 500 000 tonnes of aircraft aluminium. ‘It could save the airline industry – and other industries that use aluminium alloys – millions of dollars, as well as achieving major energy savings and reducing the world’s greenhouse gas emissions,’ Dorin states.

The process, which will also work for aluminium alloys used in the automotive, construction, marine and other industries, is both cheaper and simpler than existing options, it is claimed. ‘We can achieve the final product in only one step, and it results in reduced impurities, improved corrosion resistance and toughness – allowing the alloy to be reused for similar applications,’ Dorin points out.

Deakin University is currently seeking industry partners to progress this novel technology and ‘make aircraft recycling a reality’. According to the research team, approximately half of all aircraft are due to retire in the next 10 years.