Metal powder production by gas atomization method and double slit nozzle design

In this study, AA1070 (Etial-7) quality pure aluminum metal was atomized by gas atomization method. A double-slit nozzle with both a sonic and a supersonic region has been designed to improve the gas atomization efficiency and realize a narrower dust distribution. As is known, the nozzle geometry affects the first-order dust size and distribution. In this study, it was thought that the double slit nozzle that we originally designed could solve three main problems. The first of these is to contribute to the transmission of gas from the sonic region to the atomization region at low pressure and speed by controlling the viscosity of the liquid metal and to help the formation of smaller spherical grains. Secondly, to eliminate the solidification problem and the formation of positive pressure at the metal flow pipe end, which is one of the biggest problems of closely matched systems. The third is to prevent the closure of the gas expansion zone, also called the closed transition zone, by keeping the pressure constant with the supersonic nozzle geometry. With the double slit nozzle integrated into the gas atomization system, we can calculate the production parameters (gas pressure, melting temperature, flow pipe diameter, etc.) by optimizing, aluminum metal powders with high added value have been produced. At the end of the study, it was determined that the average grain size of the powders produced in the study using argon gas at a pressure of 35 bar, a melting temperature of 830 °C and a 3 mm flow pipe for optimal efficiency was 25,4 microns and the powder shape was spherical by 97%.