Researchers develop 'programmable', 'elasto-magnetic' materials

Amherst, Massachusetts – A team of researchers from the University of Massachusetts Amherst have engineered a new elastomer that can absorb and release ‘very large quantities of energy’.

The “rubber-like solid material” is also programmable, making it suitable for applications in self-powered robots as well as helmets and protective gears that can dissipate energy quickly.

The new 'metamaterial' combines an elastic, rubber-like substance with tiny magnets embedded in it, explained the university in a 2 Feb announcement. 

The “elasto-magnetic” material takes advantage of a physical property known as a phase shift to amplify the amount of energy the material can release or absorb.

A phase shift occurs when a material moves from one state to another – such as water turning into steam or liquid concrete hardening into a sidewalk. 

Whenever a material shifts its phase – which could also include from one solid state to another – energy is either released or absorbed. 

A phase shift that releases energy can be harnessed as a power source but according to Massachusetts Amherst producing enough energy has always been the difficult part.

“To amplify energy release or absorption, you have to engineer a new structure at the molecular or even atomic level,” said Alfred Crosby, professor of polymer science and engineering at UMass Amherst and the paper’s senior author.

Even more challenging is to do so “in a predictable way,” Crosby added. 

The metamaterial helps overcome these challenges.

“We have not only made new materials, but also developed the design algorithms that allow these materials to be programmed with specific responses, making them predictable,” Crosby noted.

By embedding tiny magnets into the elastic material, the team has managed to control the phase transitions of the metamaterial, explained lead author Xudong Liang.

“And because the phase shift is predictable and repeatable, we can engineer the metamaterial to do exactly what we want it to do,” Liang added.

This could include both absorbing the energy from a large impact, or releasing great quantities of energy for explosive movement. 

The research was supported by the US Army Research Laboratory and the US Army Research Office as well as Harbin Institute of Technology, Shenzhen (HITSZ).

Applications for the material include any scenario where either high-force impacts or lightning-quick responses are needed.