Researchers have developed a new 3-D printing method to create objects that change shape when exposed to heat.
The researchers created the objects by printing layers of shape memory polymers with each layer designed to respond differently when exposed to heat.
“This new approach significantly simplifies and increases the potential of 4-D printing by incorporating the mechanical programming post-processing step directly into the 3-D printing process,” said Professor Jerry Qi of the George W. Woodruff School of Mechanical Engineering at Georgia Tech.
“This allows high-resolution 3-D printed components to be designed by computer simulation, 3-D printed, and then directly and rapidly transformed into new permanent configurations by simply heating.”
These 4-D objects could enable a range of new product features, such as products that could be stacked flat or rolled for shipping and then expanded once in use.
The innovation could mean components capable of responding to stimuli such as temperature, moisture or light being used to create structures in space, deployable medical devices, robots and toys.
“Our composite materials at room temperature have one material that is soft but can be programmed to contain internal stress, while the other material is stiff,” said Zhen Ding, a postdoc researcher at Singapore University of Technology and Design.
“We use computational simulations to design composite components where the stiff material has a shape and size that prevents the release of the programmed internal stress from the soft material after 3-D printing. Upon heating the stiff material softens and allows the soft material to release its stress and this results in a change – often dramatic – in the product shape.”
The research reported in the journal Science Advances, was the result of a collaboration between Georgia Institute of Technology, Singapore University of Technology and Design (SUTD) and Xi’an Jiaotong University in China.