When a material is being stretched, it usually becomes thinner in the axis perpendicular to the direction of the pulling force. However, contrary to common materials, when pulled, auxetic materials expand in all directions, or when compressed they shrink in all directions.
Heat-Active Auxetic Materials, developed at MIT’s Self-Assembly Lab, are materials that exhibit auxetic behavior when exposed to heat. Compared to traditional auxetic materials, heat-active auxetic materials demonstrate autonomous performance, environmental response, easy customization, and greater possibilities for the design and fabrication of material properties.
Auxetic materials paint a picture for the future of customizable foams, crash protection, packaging materials, clothing or various other applications that relay on material stretch and compression. Imagine if these materials could be designed to transform autonomously based on temperature, moisture or light with unique stretch or compression properties that are unheard of in today's traditional materials.