Image: https://doi.org/10.1101/2023.08.07.552292
Researchers at ETH Zurich have developed a new 3D printing technology called SonoPrint, which uses sound waves to precisely arrange microparticles in three-dimensional structures. The process combines volumetric 3D printing with acoustic manipulation and enables the production of composite materials with improved mechanical properties.
The technique uses ultrasonic waves to arrange microparticles of glass, metal or polystyrene in a light-sensitive resin. By controlling the sound waves, various patterns such as parallel lines, circles or hexagons can be created. The entire volume is then cured in a few minutes by projecting light images.
The scientists tested different particle sizes from 1 to 250 micrometres. Depending on the configuration of the ultrasonic transducers, line spacings of between 0.46 and 0.96 millimetres could be generated. Mechanical tests showed that samples with aligned particles had a 46 per cent higher tensile strength than those with randomly distributed particles.
One advantage of the process is that it is independent of the electrical or magnetic properties of the particles. This means that a wider range of materials can be processed than with previous techniques for particle alignment in 3D printing.
The researchers see potential applications in aerospace, medical technology and tissue engineering. As a next step, they plan to create selective patterns in different areas of a component in order to further optimise its properties.
The study was published in the scientific journal Advanced Materials. The technology is still at the research stage, but could open up new possibilities for the production of customised composite materials in the future.