Drop-on-demand electromagnetic printing of metallic droplets

A drop-on-demand electromagnetic printing process has been developed to deposit metallic droplets. An external electromagnetic field and an internal pulsed current pass through the metallic liquid are introduced to make the liquid driven by the resulting electromagnetic force. Experimental results show that the printing frequency equals to the power frequency, and can be larger than 150 Hz when the pulsed width is 5 ms. The printed mercury droplets are uniform in diameter with a mean variation of 2.27%. Smaller nozzle, shorter pulse width and lower magnetic field intensity favor tiny droplets. Besides, printing of molten solder at a temperature of 290 °C is achieved. Our results show promise for electromagnetic printing as a potential tool in drop-on-demand printing fabrication of high-melting-point metals.