Method and device for producing heavy metal powders by ultrasonic atomization

A device for production of heavy metal powders by ultrasonic atomization from a heavy metal raw material that comprises an electrically conductive metal having a density>8500 kg/m3 and a melting temperature (liquidus)>1073 deg K=800 C at 1 barA, the device comprising:

• feeding means for providing the heavy metal raw material in the vicinity of a heat source;
• wherein the heat source has an electrode and generates an electric arc to heat the heavy metal raw material so as to create a molten metal pool on a sonotrode, wherein the molten metal pool has a temperature equal to or greater than the melting temperature of the heavy metal raw material, wherein the molten metal pool has a temperature below a vaporization temperature of the heavy metal raw material, and wherein the sonotrode provides ultrasonic mechanical vibrations to the molten metal pool, so as to cause heavy metal droplets to be ejected from the molten metal pool;
• an adjusting means comprising at least one processor and at least one memory and configured to adjust feeding means parameters of the feeding means, adjust heating means parameters of the heating means, and adjust sonotrode parameters of the sonotrode to direct the heavy metal droplets away from the molten metal pool, so as to cause the heavy metal droplets to freely cool down at least by radiation within a predetermined distance and transform the heavy metal droplets to the heavy metal powder;
• collecting means for collecting the heavy metal powder;
• wherein the electrode is a cathode;
• wherein the sonotrode is an anode;
• wherein the electric arc is of the length in the range from 5 mm to 40 mm;
• wherein the electric arc length is measured between a tip of the cathode and a center of the sonotrode;
• wherein a power supplied to the electric arc does not exceed 15 KW per 1cm2 of the area of the molten metal pool;
• wherein the velocity of the ultrasonic mechanical vibrations on a hot end of the sonotrode is at least 0.2 m/sec 0-peak in a frequency range of 15 kHz to 1000 kHz so that at least 75% of the heavy metal raw material in the form of the heavy metal powder is collected by the collecting means.