Researchers at the Swiss Federal Institute of Technology (EPFL) in Lausanne have developed a novel method of growing metals and ceramics using 3D printing technology, which they say can produce “exceptionally dense” materials up to 20 times stronger than average.
The breakthrough relies on printing materials within a water-based gel, which they say can now produce remarkably strong metals and ceramics. These have potential applications in cutting-edge energy and defense systems, as well as remote sensing and biomedical applications.
The EPFL team’s research was detailed in a new paper that was published in Advanced Materials.
3D Printing Exceptional Metals
The breakthrough relies on a process known as vat photopolymerization, used in 3D printing. This process involves pouring resins sensitive to light into a vat and hardening them into their final shape using lasers and UV light exposure.
Since this technique generally only works with photosensitive polymers or resins, it has seen limited use in practical applications. Nonetheless, there are a few 3D printing methods that have shown promise in the conversion of these polymers into far more useful materials, such as extra-dense metals and ceramics.
“These materials tend to be porous, which significantly reduces their strength, and the parts suffer from excessive shrinkage, which causes warping,” according to Daryl Yee, who leads EPFL’s Laboratory for the Chemistry of Materials and Manufacturing within the institute’s School of Engineering.
Because of this, such materials have seen limited use in the past due to their structural issues. Now, that is all set to change as Yee and his research team have developed a novel method of improving the quality of these polymer-based materials.
A Hydrogel Solution
For their new process, Yee and his team relied on unique substances known as hydrogels. These hydrogels can be used to create a 3D scaffold, after which the hydrogel is infused with metal salts that are transformed into nanoparticles possessing metals that permeate the structure.
By contrast, past methods would normally rely on the use of resins that have been infused with metal precursors, which are hardened using light. The new process relies on a chemical conversion, which the researchers say can be repeated to produce composite materials with extremely high concentrations of metals.
The researchers say that this method induces between five and ten cycles where the material is “grown” during chemically induced cycles, after which it is heated to burn away any remaining hydrogel material left over from the growth process. The result is an object made of the desired metal or ceramic, shaped like the “blank” polymer used at the outset of the process.
The resulting materials, in addition to having the desired shape, are also exceptionally strong.
“Our work not only enables the fabrication of high-quality metals and ceramics with an accessible, low-cost 3D printing process,” Yee said in a statement. “[I]t also highlights a new paradigm in additive manufacturing where material selection occurs after 3D printing, rather than before.”
Additionally, the team says its new technique is extremely versatile, as it enables a hydrogel sample to be transformed into various types of metals, ceramics, or composites. This occurs because the material only undergoes infusion of the metal salts after fabrication.
The Future of Advanced 3D Printing
As demonstrations of their new technique, the team successfully produced shapes called gyroids, recognized for their intricacy, with examples composed of iron, copper, and even silver.
Subsequent tests confirmed that each of the samples produced from these materials was exceptionally strong.
“Our materials could withstand 20 times more pressure compared to those produced with previous methods, while exhibiting only 20% shrinkage versus 60-90%,” said Yiming Ji, an EPFL PhD student and first author of the team’s recent study.
One particularly promising aspect of the research is the development of materials that combine the benefits of remarkable strength with lightweight and complex properties. These materials could have a range of potential applications in devices used for energy conversion, storage, sensing technologies, and other areas.
Going forward, the team says they plan to make further improvements to the process, which they hope will increase the strength of the materials they produce even more. Additionally, they aim to reduce the overall processing time required for their new technique, which Yee says may be achievable by introducing robots to automate certain steps in the production process.
The team’s research study, “Hydrogel-Based Vat Photopolymerization of Ceramics and Metals with Low Shrinkages via Repeated Infusion Precipitation,” appeared in Advanced Materials on September 24, 2025.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.