Oregon State University’s College of Engineering researchers have made progress in the ability to rapidly manufacture flexible electronics and soft robotics.
Flexible computer screens would undoubtedly be a cool improvement to laptops, hopefully making them more difficult to crack. Amazingly, this isn’t an impossible dream. Researchers from Oregon State University’s College of Engineering are getting closer to making this a reality.
The researchers, from the college’s Collaborative Robotics and Intelligent Systems Institute, are getting closer to being able to 3D print stretchable electronic devices, soft robots, and flexible computer screens.
Using a highly conductive gallium alloy, the team is working on 3D printing tall, complicated structures. To make the liquid metal Galinstan suitable for 3D printing, they thicken it to a paste using nickel nanoparticles and sonication (the energy of sound).
“The runny alloy was impossible to layer into tall structures. With the paste-like texture, it can be layered while maintaining its capacity to flow and to stretch inside of rubber tubes. We demonstrated the potential of our discovery by 3D printing a very stretchy two-layered circuit whose layers weave in and out of each other without touching,” Yiğit Mengüç, assistant professor of mechanical engineering and co-corresponding author on the study.
3D Printing Gallium Alloys
The benefits of using a gallium alloy are that it has low toxicity, good conductivity, and is cheap. As a result, the alloys are already in use for flexible electronics as the conductive material.
However, before the researchers used sonication to mix nickel particles and the oxidized gallium to create a paste, printing was restricted to 2D. But, the team can now print structures up to 10 millimeters high and 20 millimeters wide.
The gallium alloy paste offers new features to the flexible electronics field. In fact, the alloys are “self-healing” which means that at breakpoints, they’re able to attach back together.
The researchers also add that it is quick and easy to make. Better yet, its structural change is permanent and the electrical properties are similar to pure liquid metal.
“Liquid metal printing is integral to the flexible electronics field… Additive manufacturing enables fast fabrication of intricate designs and circuitry,” said co-author Doğan Yirmibeşoğlu, a robotics Ph.D. student at OSU.
Yirmibeşoğlu adds that with the gallium alloy, “the future is very bright”. He explains that someday we should see soft robots coming out of the printer which are ready for action.
The researchers are now working on the exact structure of the gallium alloy paste. They’ll learn about how the nickel particles are stabilized. But, they’ll also continue to observe any changes in the paste as it ages.
Want to find out more? The researchers recently published their findings in Advanced Materials Technologies.
Source: Science Daily