Researchers want to improve 3D printing with microwave technology

With a new 3D printing process that a team at Lawrence Livermore National Laboratory (LLNL) calls Microwave Volumetric Additive Manufacturing (MVAM), researchers have introduced an innovative new approach to 3D printing that uses microwave energy to cure materials, opening the door to a wider range of materials than ever before.

While light-based processes such as Computed Axial Lithography (CAL) can print complex structures quickly, they rely on transparent resins. MVAM, on the other hand, enables the processing of opaque and filler materials, which significantly expands the potential of 3D printing.

“I think this is going to revolutionize the way people look at additive manufacturing,” said Mukherjee, who specializes in applied electromagnetics. “If we think about a lot of applications—aerospace, automotive, nuclear industry—their geometries are simple, but they are large and they need rapid prototyping. One major impact [of MVAM] is if we can maintain a feedstock of materials surrounded with a microwave antenna array, we can now think about creating simple large geometries, as well as complicated large geometries, at scale using microwaves.”

In order to optimise the efficiency of this process, the researchers have developed a multiphase model that simulates the interaction of microwaves with different materials. This allows the energy input and curing time to be precisely controlled. In experiments, the researchers showed that resins, which previously took around two and a half minutes to cure, could be processed within six seconds at a power of one kilowatt.

“Microwave volumetric AM opens up a new frontier in 3D printing by enabling the use of opaque and filled materials, which were previously challenging to work with,” Co-author Maxim Shusteff, co-inventor of the original visible light-based CAL approach, said, “This can be a path toward large-format parts with enhanced material properties.”

In addition to faster production, MVAM also enables the manufacture of components with integrated functions, such as sensors or conductive paths. This versatility could have the potential to fundamentally change manufacturing in areas such as aerospace and medical technology. Researchers are currently working on making the process more cost-efficient to make it more attractive for industrial applications.

“With have a unique opportunity to expand the definition of what is ‘printable,’ accessing chemistries previously not possible in light-based systems,” Co-principal investigator Johanna Schwartz, the team’s chemistry lead, said. “This is a whole new printing space, and so our ongoing progress is just extremely exciting.”

“We are looking at how we can custom design or custom build some of these circuits or hardware by ourselves so that we can reduce a lot of cost and show that the overall concept works before big projects or outside external sponsors are willing to invest in this technology.”