| 摘要 |
PURPOSE:To prevent oxidation during atomizing and to perform spray casting without macro segration by ejecting liquid hydrogen to the molten metal flow falling downward from a vessel for molten metal, and capturing the liquid drop which is internally melted in a casting mold. CONSTITUTION:Molten steel is charged through a vessel such as a ladle 1 or a tundish 2 to the center of a liquid dropping nozzle 3. On the other hand, the liquid hydrogen of an ultralow temp. supplied from the nozzle 3 is ejected toward charging molten steel flow 5. The molten steel flow is made into fine liquid drops here and the liquid hydrogen colliding against the molten steel evaporates simultaneously with the collision. The pulverized steel particle falls toward a casting mold 7 while dispersing slightly. The molten steel flow under falling is cooled by the liquid hydrogen and the evaporated gaseous hydrogen of a low temp so that the molten steel is captured in the semi-solidified state having partly solidified surface skin and is charged into the mold 7. A cast ingot is obtd. after cooling. Since this operation is accomplished in a casting chamber 8, the operation in a gaseous hydrogen atmosphere is possible without causing any problem that arises in oxidation. |
