I don’t think anybody questions the fact that 3D printing has done and continues to do amazing things. The questions being asked now are about how we can continue to push the possibilities forward. One of the arenas for investigation involves the possibilities for printers to print with more than one material at a time. Currently, each time a material is switched, the printing process has to be stopped. In order to address this, researchers at Harvard University worked to create a printhead that can mix and print viscoelastic inks.
In order to understand the developments required to create this technology, it is first necessary to explain the
Active mixing adds the use of a rotating impeller to ‘encourage’ the mixture by moving the two previously disparate liquids about within the same space, in this case a microscale nozzle. Director of the Lawrence Livermore National Lab’s Center for Engineered Materials, Manufacturing and Optimization, Christopher Spadaccini explained the way in which this advances materials research:
“The recent work by the Lewis Group is a significant advancement to the field of additive manufacturing. By allowing for the mixing of two highly viscous materials on the fly, the promise of mixed material systems with disparate mechanical and functional properties becomes much more realistic. Before, this was really only a concept. This work will be foundational for applications which required integrated electrical and structural materials.”
The research team itself demonstrated several potential applications of their technological development such as the printing of silicone elastomers into gradient architectures with some regions having a greater plasticity than others. In addition, reactive materials, such as epoxies that are designed to harden when mixed were able to be used for printing through this process.
Lewis and her team are confident that these developments will create a range of new possibilities for 3D printing, noting:
“Together, these active mixing and switching printheads provide an important advance for multimaterial 3D printing. They allow one to programmably control both materials composition and structure at the microscale, opening new avenues for creating materials by design.”
Let’s hear your thoughts on this research in the 3D Printing Materials forum thread on 3DPB.com.