Glass possesses excellent transparency as well as stability when it encounters chemicals or heat and is thus considered right for several high-tech applications. But traditional processes involved in shaping glass are known to be tiresome, energy-intensive, and rapidly reach their limits for compact and complex components.
The materials scientists from University of Freiburg, Dr. Frederik Kotz-Helmer and Prof. Bastian E. Rapp, in collaboration with the University of California at Berkeley, have come up with a novel process that could be used to rapidly and accurately generate very small components from transparent glass with the help of micro 3D printing. Feasible applications incorporate components not only for sensors and microscopes but also for lab-on-a-chip systems.
The new technology relies on the so-called Glassomer materials, which were jointly developed by Kotz-Helmer and Rapp at the Department of Microsystems Engineering (IMTEK) at the University of Freiburg. Furthermore, the consequent components are placed in a furnace, making the plastic burn and the glass sintered.
Currently, the Freiburg scientists have integrated Glassomer materials with the help of a new 3D printing process developed by a research group headed by Prof. Hayden Taylor from the University of California, Berkeley. Traditional 3D printers will print their objects using a layer-by-layer method. But in the new process, called computed axial lithography (CAL), the component is made in a single step.
A vessel consisting of liquid and light-sensitive material has been exposed to two-dimensional light images of the object to be printed from several different angles. Here, there is an overlap of the images and the amount of light absorbed, therefore, surpasses a few thresholds locally. The material toughens suddenly, in just a matter of minutes, and the component is formed. The surplus, still liquid material could then be washed off.
Currently, it is possible to combine and improve these technologies by integrating the materials science ability at the University of Freiburg and the project partner Glassomer GmbH, a Freiburg spin-off, as well as the additional development of the system technology at the University of California.
Kotz-Helmer believes that this inventive manufacturing process has many possible applications, for instance, in virtual reality headsets and in micro-optical components of sensors and modern microscopes.
Furthermore, microfluidic channels are required for the alleged lab-on-a-chip systems in the field of research and medical diagnostics. So far, these have primarily been made of plastics, but they cannot resist harsh chemicals and high temperatures. As a result of the new process technology, complicated channel systems can currently be manufactured in glass
For more information: University of Freiburg
