| 摘要 |
PURPOSE:To prepare a metal material extremely reduced in segregation, by a method wherein a molten metal is flowed down to be introduced into a vacuum container while a specific amount or more of gas is contained in said molten metal and converted to liquid droplets by the expansion of the gas to be deposited on a solid collector. CONSTITUTION:A molten metal 1 such as 13% Cr stainless steel is placed in an H2-gas or N2-gas atmosphere and at least 5ppm or more of this gas is contained in the molten metal 1. This molten metal 1 is introduced into a tandish 2 and flowed down into a vacuum spray tank 4 from a nozzle 5. The flowing-down molten metal stream is formed into small liquid droplets 7 by the expansion of the H2- or N2-gas contained therein in the spray tank evacuated to 200Torr or less and deposited on a dish shaped collector 8 made of refractory such as alumina. In this case, the position of the solid collector 8 is moved up and down to adjust the distance from the nozzle 5 and the metal liquid droplets are successively deposited on the collector 8 in such a state that only the surface part of each droplet is melted or semi-melted but the interior thereof is coagulated to enable the formation of a deposited metal material 9 extremely reduced in componential segregation. |
