The capacity of lightweight materials to reduce the transportation sector’s carbon footprint could be erased if their production isn’t efficient too. That’s why the EU-funded RECOTRANS project has developed a state-of-the-art process to manufacture composite components for cars, trains and trucks. Innovations such as these will help the EU reach its climate goals, securing a healthy environment for all citizens. 

While transportation plays a critical role in society and the economy, it does so at a significant cost to the environment. In fact, the transportation sector is responsible for nearly a quarter of Europe’s total greenhouse gas emissions, making it a major driver of climate change. The sector also has the unwelcome distinction of being the leading cause of air pollution in urban areas.

More efficient manufacturing processes

If Europe is to meet its goal of reducing carbon emissions by at least 55% by 2030, the transportation sector must clean up its act. Not only does this require the use of more efficient vehicles, it also means developing more efficient manufacturing processes.

The EU-funded RECOTRANS project aims to do both.

“On one hand, integrating lightweight materials into vehicle designs helps reduce overall weight, thus allowing the vehicle to go further using less energy,” said Rocío Ruiz Gallardo, a researcher with the Sustainable and Future Mobility Group, one of the project’s lead partners. “On the other hand, if the manufacturing process isn’t efficient, you essentially cancel out the material’s energy savings.”

To address these twin issues, the project developed a state-of-the-art process for manufacturing lightweight materials for the transportation sector. “Our process uses unconventional manufacturing technologies like microwave radiation and laser joining to create thermoplastic composite materials,” said Ruiz.

Thermoplastic composites lack the chemical instability of traditional polymer composites. This means they can be easily softened with heat and moulded into a desired shape without degrading the material’s integrity. Once cooled, the material solidifies into the finished shape, such as a car door, truck suspension system, or train interior panel.

“Because composite materials are stronger and lighter than traditional materials, they can reduce a vehicle’s weight by as much as 30%,” said Ruiz. “Such a saving in weight translates into both energy savings and increased performance.”

According to Ruiz, RECOTRANS’ composites have the added environmental benefit of being made from a thermoplastic resin, developed by project partner Arkema, that allows the products to be recycled. “Not only are these lightweight vehicle parts more sustainable, at the end of their life, they can be recycled into new products and parts, thus enabling a circular economy,” she added. 

RECOTRANS has developed several innovative technologies. To ensure high-volume production, the project uses microwave technology for both resin transfer moulding and pultrusion manufacturing lines.

“This novel manufacturing method creates an opportunity to increase production rates by accelerating the polymerisation time of the thermoplastic resin,” says Ruiz. “This reduction in cycle time enables a reduction in total energy consumption.”

RECOTRANS also used laser joining technology to develop a cost-effective joining method for polymer-metal composites, reducing the weight of components by fully integrating the composite to the metal part.

Efficiency and cost savings

Based on initial assessments, the efficiency and cost savings of the system are remarkable. For instance, on the manufacturing side, the RECOTRANS system can reduce production time from 10-50%, and costs by up to 35%. Furthermore, it is estimated that the use of these technologies can cut energy consumption by 10%.

As to the composite parts being produced, Ruiz said end users stand to benefit too: “Compared to equivalent conventional metal parts, our composite parts will result in a significant weight reduction for autos, trucks and rail, which could translate into important economic savings.”

To put some figures behind these claims, RECOTRANS estimates a reduction in weight for trucks, automobiles and rail of 64%, 63% and 57% respectively. Furthermore, the economic savings (per part) for buyers and users can be as much as €40.80 for truck parts, €2.10 for automobile parts and €6.60 for rail parts.

And let’s not forget the environmental benefits of using these lightweight parts. “Our composite parts have the potential to reduce a vehicle’s CO2 emissions by as much as 39.8 kg for trucks and 40.3 kg for autos,” said Ruiz. “Such reductions will ensure that the transportation sector delivers on the promises made in the European Green Deal.”