New 3D-printed material could lead to lighter, safer vehicles

8 Feb 2021

Plate-lattice structure. Image: University of Glasgow

Engineers have developed a new 3D-printed material that could be both tougher and lighter than similar types of aluminium.

Material scientists are often searching for ways to create materials that are more durable, more flexible or more lightweight. Now, a team led by University of Glasgow engineers has developed a new form of 3D-printed material that could be both tougher and lighter than similar types of aluminium.

In a paper published in Materials & Design, the researchers describe how they have developed a new plate-lattice cellular metamaterial capable of impressive resistance to impacts.

The material could lead to the development of safer, lighter and more durable structures for use in the aerospace, automotive, renewables and marine industries.

Metamaterials are artificially created cellular solids, designed to manifest properties that don’t occur naturally.

One form of metamaterial, known as plate-lattices, are cubic structures made from intersecting layers of plates that exhibit unusually high stiffness and strength. They are also unusually lightweight, due to a significant amount of space between the plates.

The University of Glasgow researchers set out to investigate whether new forms of plate-lattice design, manufactured from a plastic-nanotube composite, could make a metamaterial with even more advanced properties of stiffness, strength and toughness.

The composite uses mixtures of polypropylene and polyethylene and multiwall carbon nanotubes. The scientists used their nanoengineered filament composite as the feedstock in a 3D printer, which fused the filaments together to build a series of plate-lattice designs.

Those designs were then subjected to a series of impact tests by dropping a 16.7kg mass from a range of heights to determine the ability to withstand physical shocks.

‘The intersection of mechanics and materials’

Dr Shanmugam Kumar of the University of Glasgow’s James Watt School of Engineering led the research project. The team also involved mechanical and chemical engineers from Khalifa University in Abu Dhabi and Texas A&M University in the US.

Kumar said this work sits at “the intersection of mechanics and materials”.

“In the pursuit of lightweight engineering, there is a constant hunt for ultra-lightweight materials featuring high performance. Our nanoengineered hybrid plate-lattices achieve extraordinary stiffness and strength properties and exhibit superior energy absorption characteristics over similar lattices built with aluminium,” he said.

“One application for this new kind of plate-lattice might be in automobile manufacture, where designers perpetually strive to build more lightweight bodies without sacrificing safety during crashes. Aluminium is used in many modern car designs, but our plate-lattice offers greater impact resistance, which could make it useful in those kinds of applications in the future.”

He added that the recyclability of the plastics used also makes them attractive in the move towards a more circular economy.

Jenny Darmody is the editor of Silicon Republic