Method of producing metal powder

Abstract

A method of producing metal powder, in which molten metal which is stored in a molten metal holding furnace is atomized using, a molten metal nozzle upward to generate fine liquid droplets from the molten metal and the droplets are rapidly solidified by cooling, including: preparing at least one metal melting furnace which is configured to melt metal to form molten metal, and a molten metal holding furnace which has a trough which receives the molten metal and sends the received molten metal into the molten metal holding furnace, atomizing molten metal which is stored in the molten metal holding furnace upward by a molten metal nozzle to generate fine liquid droplets of the molten metal and rapidly solidifying the droplets by cooling to produce metal powder, and controlling a molten metal level of the molten metal in the molten metal holding furnace by melting metal in the metal melting furnace to form molten metal and supplying the molten metal to the trough from the metal melting furnace.

1 . A method of producing metal powder, in which molten metal which is stored in a molten metal holding furnace is atomized using a molten metal nozzle upward to generate fine liquid droplets from the molten metal and the liquid droplets are rapidly solidified by cooling, comprising:
 preparing at least one metal melting furnace which is configured to melt metal to form molten metal, and a molten metal holding furnace which has a trough which receives the molten metal and sends the received molten metal into the molten metal holding furnace;   atomizing molten metal, which is stored in the molten metal holding furnace, upward by a molten metal nozzle to generate fine liquid droplets of the molten metal, and rapidly solidifying the droplets by cooling to produce metal powder; and   controlling a molten metal level of the molten metal in the molten metal holding furnace by melting metal in the metal melting furnace to form molten metal and supplying the molten metal to the trough from the metal melting furnace.   
     
     
         2 . The method of producing metal powder according to  claim 1 , wherein the molten metal is molten aluminum or a molten aluminum alloy. 
     
     
         3 . The method of producing metal powder according to  claim 1 , wherein a pair of the metal melting furnaces is prepared, and when one of the metal melting furnaces supplies the molten metal, which is melted in the metal melting furnace, to the trough, the other metal melting furnace melts metal without supplying the molten metal to the trough. 
     
     
         4 . The method of producing metal powder according to  claim 1 , wherein the metal melting furnace is controlled in such a manner that the molten metal is supplied to the trough so that a variation of molten metal included in the molten metal holding furnace is controlled in a range of ±170 mm. 
     
     
         5 . The method of producing metal powder according to  claim 1 , wherein the step of controlling the molten metal level includes
 a measuring step of measuring the molten metal level of molten metal in the molten metal holding furnace or the trough, and   a step of supplying the molten metal in the metal melting furnace to the trough when the molten metal level measured in the measuring step is lower than a specified value.   
     
     
         6 . The method of producing metal powder according to  claim 1 , wherein the step of controlling the molten metal level includes
 a measuring step of measuring the molten metal level of molten metal in the molten metal holding furnace or the trough, and   a step of not performing supply of the molten metal in the metal melting furnace to the trough, when the molten metal level measured in the measuring step is larger than a specified value.   
     
     
         7 . The method of producing metal powder according to  claim 2 , wherein a pair of the metal melting furnaces is prepared, and when one of the metal melting furnaces supplies the molten metal, which is melted in the metal melting furnace, to the trough, the other metal melting furnace melts metal without supplying the molten metal to the trough. 
     
     
         8 . The method of producing metal powder according to  claim 2 , wherein the metal melting furnace is controlled in such a manner that the molten metal is supplied to the trough so that a variation of molten metal included in the molten metal holding furnace is controlled in a range of ±170 mm. 
     
     
         9 . The method of producing metal powder according to  claim 3 , wherein the metal melting furnace is controlled in such a manner that the molten metal is supplied to the trough so that a variation of molten metal included in the molten metal holding furnace is controlled in a range of ±170 mm. 
     
     
         10 . The method of producing metal powder according to  claim 7 , wherein the metal melting furnace is controlled in such a manner that the molten metal is supplied to the trough so that a variation of molten metal included in the molten metal holding furnace is controlled in a range of ±170 mm.