Researchers now hope to make glass with a more versatile, modern-day technology: 3-D printing. In a study published in Nature on Wednesday, a team from Germany presented a new glassmaking method based on a âliquid glassâ that can be shaped into complex structures with a 3-D printer, and then heated into a solid. The technique may reduce the time and costs of creating complex or detailed glass pieces, and yield high-quality glass that is smooth enough to make lenses and mirrors, said Bastian Rapp, a principal investigator at the Karlsruhe Institute of Technology, and an author of the paper.
Three-dimensional printing is more pervasive than ever, yet it remains mostly limited to plastics, ceramics and metals. People thought glass would just not be accessible to 3-D printing, Dr. Rapp said. âWe wanted to close this important material gap.â
Other groups have 3-D-printed glass, including an Israeli company called Micron3DP and a group led by Neri Oxman at M.I.T.âs Media Lab. But Dr. Rappâs approach is different, according to Michael Petch, editor in chief of the website 3D Printing Industry. The other two approaches involve melting and laying down strands of material, sort of as you would with a glue gun. Extruding the glass in layers makes it difficult to create a smooth, transparent object, Mr. Petch said.
Dr. Rappâs team used a method called stereolithography, which involves shaping structures with UV light. They loaded a high concentration of glass nanoparticles into whatâs called a photocurable liquid, which hardens under UV light. The mixture sits in a container and is exposed, slice by slice, to UV light that has been programmed to create different shapes at each layer. The regions that are exposed become solid. Heating the structure in a high-temperature furnace, like a ceramics kiln, burns away the leftover liquid and fuses the glass nanoparticles together.
Creating unique or intricate glass shapes this way has the potential to be much easier, and orders of magnitude cheaper, than the methods commonly used today, Dr. Rapp said. Currently, shaping large glass structures…