New technique allows you to create complex, light and resistant structures; they will be used for sensors, biomedical implants and other devices.
Researchers in Switzerland have developed a innovative 3D printing technique that “grows” metals and ceramics inside a gelallowing the creation of complex, light and resistant structures, suitable for sensors, biomedical implants and other advanced devices.
A , used by École Polytechnique Fédérale de Lausanne (EPFL), uses a standard in-vat photopolymerization printer — an accessible and low-cost technology — to first produce a light-cured hydrogel structure.
This blank model is then infused with metallic ions through a process the team calls “infusion-precipitation”, opening a new approach in additive manufacturing, where material selection occurs after printing.
The hydrogel models are immersed in metallic salt solutions at 65.° C, allowing metal ions to penetrate the gel. These ions are then converted into nanoparticles using a precipitating agent. Repeating this cycle several times increases the density of metal nanoparticles in the gel. Finally, the structure is heated to remove the hydrogel and sinter the nanoparticles, resulting in a solid metal or ceramic object that replicates the original shape.
With this method, explains , researchers were able to fabricate complex gyroid lattice structures in iron, silver, copper and the magnetic ceramic strontium hexaferrite (SrFe₁₂O₁₉). The resulting materials were 20 times more resistant than those produced by previous polymer-to-metal methods, showing only about 20% shrinkage — a significant improvement over the typical 60–90%.
This minimal deformation allows the production of flatter and more stable parts, such as gears and tubular stents, essential in biomedical and mechanical devices. “The reduction in deformation achieved with our process expands the range of parts that can be manufactured,” said Daryl Yee, principal investigator.
The team is working on automating these steps with robotics to speed up production — paving the way for a scalable, low-cost manufacturing of high-performance metals and ceramics.
