RApid prototyping of 3D microstructures by direct printing of liquid metal at temperatures up to 500°C using the starjet technology

We present a novel approach for 3D-prototyping of porous metal structures by direct non-contact liquid metal printing, based on the StarJet technology [1]. In contrast to our previous work, the presented droplet generator features an improved nozzle chip design and actuator housing that allows operation at temperatures up to T_max = 500°C (formerly T_max = 250°C). This enables the ejection of single droplets of metals with higher melting points like for example magnesium or zinc alloys like ZAMAK. The droplet generation frequency could be increased by a factor of 10 to f_max = 4 kHz. Furthermore, deviations of the droplet trajectory from the symmetry axis of the nozzle are reduced to Δdeg = 0.28° by the new design. This paper reports on experimental results obtained with the improved device and presents 3D metal structures with various porosities.