John Tolley, November 10, 2016

It?s fair to say the students in Dr. Pablo Zavattieri?s Lab at Purdue have a crush on their work.

That?s kind of the point.

Zavattieri and his students are working with PXCMs, or phase transforming cellular materials. PXCM?s can absorb energy while still retaining a stable shape, making them ideal for use in the construction of bridges and buildings, for sport equipment like football pads and helmets, and in automobile design.

"The main advantage is that not only can it be used as an energy absorbing material,? said Zavattieri, speaking with the Purdue News Service, ?but unlike many other materials designed for this purpose the PXCMs would be reusable because there is no irreversible deformation.?

Taking inspiration from some unlikely sources, like origami objects and bendy straws, students use computer modeling and computer-aided design to help visualize PXCM structures. Like those bendy straws, PXCM can flex between two different shapes and can hold in either indefinitely. It is this property that allows for PXCMs, used in conjunction with each other, to dissipate energy upon impact. These materials are also resilient and could be manufactured cheaply.

"With current materials, the energy dissipation occurs with significant damage to the material, damage that is often permanent," explained junior Gordon Jarrold. "The goal for our project is to contribute to the lab's efforts to develop new materials that are reusable even after a significant energy dissipation event."

With funding from General Motors and the National Science Foundation, Zavattieri?s team is creating a PXCM that can be easily produced using 3D printing technology. Its work that he said wouldn?t be possible without the help of his students.

"I have found it very valuable to have excellent undergraduates in the lab who are curious. They are passionate about contributing to the research we are doing, asking a lot of questions and challenging us every day. What's more, these students are playing key roles in a type of work that breaks the stereotypes of civil engineering research, which can be as unpredictable and exciting as other engineering disciplines in terms of what the future holds."