New direct metal printing technology enables flexible and self-healing electronics
Researchers at the University of North Carolina have developed a new direct metal printing technology ideal for making electronic circuits that can stretch, shrink, and have self-healing functions. The new technology makes it possible to print circuits with several types of metal alloys on various types of substrates. Moreover, this technology is fully compatible with existing production systems of this kind.
The basis of the new technology is a fairly widespread technology of electrohydrodynamic printing. Only now metal alloys are used as ink for this printing, the melting point of which is about 60 degrees Celsius. Scientists have demonstrated the capabilities of this printing technology by creating electronic elements from three different alloys on a glass base, on paper and on two types of elastic polymer material.
“Our process is exclusively a printing process. It does not use any trimming, engraving or other machining, “the researchers write. This makes our new process the most” straight forward “of all direct metal printing methods available.”
Circuits printed on a resilient polymer base retain their integrity when bent at a sufficiently large angle over a thousand times. In addition, the electrical conductivity of the printed conductors is maintained when the circuit is stretched 70 percent of its original size.
Printed circuit components are capable of self-healing if they break from excessive bending or stretching. This property is a consequence of the low melting temperature of the metal alloy, because in places where the integrity of the conductor is broken, areas with increased resistance arise. In these places, when an electric current flows, heat begins to be released, the material of the conductor melts and its electrical conductivity is completely restored to its original value.
In addition to all the advantages listed above, the new direct metal printing technology provides a fairly good resolution. A demonstration of this was a touch sensor, on one square centimeter of which a matrix of 400 sensitive elements was printed.
“In the very near future, we hope to find interested partners from the industrial sector,” the researchers write. “Together, we will develop a new printing technology to a level acceptable for use in real production. And then, with the help of the new technology, it will be possible to organize the production of various types of sensors, wearable and embedded electronic dev
ices. “Source: www.dailytechinfo.org