The invention relates to a supersonic gas atomization spraying disc for 
metal powder preparation. The supersonic gas atomization spraying disc for 
metal powder preparation comprises a spraying disc 
upper lip and a spraying disc 
lower lip. An annular cooling water cavity is formed inside the spraying disc 
upper lip. A center hole which penetrates through the thickness of the spraying disc upper lipis formed in the center of the spraying disc 
upper lip and used for allowing a flow guide 
nozzle to be placed. A gas inlet pipeline which is used for being connected with an external gas source is arranged on the spraying disc 
lower lip. An annular gas cavity can be formed after the spraying disc 
lower lip and the spraying disc upper lip are assembled, and a 
nozzle which is of a semi-Laval structure is formed in an outlet of the annular gas cavity after the spraying disc upper lip and the spraying disc lower lip are assembled. According to the supersonic gas atomization spraying disc for 
metal powder preparation, the 
thermal deformation of the spraying disc is reduced by circulating cooling water, the sealing performance of the whole spraying disc structure is protected, and the service life of the spraying disc is prolonged. The spraying disc upper lip and the spraying disc lower lip are assembled to form the 
nozzle which is of the circular seam type semi-Laval structure, and the width of the 
throat portion of the nozzle is adjustable. According to the supersonic gas atomization spraying disc for 
metal powder preparation, a technological adjustment window is wide, the 
gas consumption is low, the gas flow inside the spraying disc is uniform, and the 
fine powder yield can be substantially improved.