ATLANTA— Engineers at the Georgia Institute of Technology have developed a printer that could streamline the creation of self-assembling structures that can change shape after being exposed to heat and other stimuli. They claim the breakthrough could accelerate the use of 4D printing in aerospace, medicine and other industries. It could also be used to print electrical wiring.
“We are on the cusp of creating a new generation of devices that could vastly expand the practical applications for 3D and 4D printing,” says H. Jerry Qi, Ph.D., a professor of mechanical engineering at Georgia Tech. “Our prototype printer integrates many features that appear to simplify and expedite the processes used in traditional 3D printing.
“As a result, we can use a variety of materials to create hard and soft components at the same time, incorporate conductive wiring directly into shape-changing structures, and ultimately set the stage for the development of a host of 4D products that could reshape our world,” claims Qi.
4D printing is an emerging technology that allows 3D-printed components to change their shape over time after exposure to heat, light, humidity and other environmental triggers.
“However, 4D printing remains challenging, because it often requires complex and time-consuming post-processing steps to mechanically program each component,” says Qi. “In addition, many commercial printers can only print 4D structures composed of a single material.”
The Georgia Tech machine combines four different printing techniques, including aerosol, inkjet, direct ink write and fused deposition modeling. Among other things, it can create electrical wiring that can be printed directly onto an antenna, sensor or other electrical device.
“The process relies on a direct-ink-write method to produce a line of silver nanoparticle ink,” explains Qi. “A photonic cure unit dries and coalesces the nanoparticles to form conductive wire. Then, the printer’s ink-jet component creates the plastic coating that encases the wire.”