PURPOSE: To form an ingot having fine and uniform structure and to uniformly disperse a machinability-improving element therein by discharging a molten metal contg. the machinability-improving element into a casting chamber, applying an inert gas to the molten metal flow to form fine drops and solidifying and depositing the fine drops on a base body.

CONSTITUTION: A ladle 2 is provided to the upper part of the casting chamber 1 and the melt of a stainless steel contg. the components corresponding to the prescribed machinability is filled therein. The molten metal is dropped as the molten metal flow 4 from a nozzle 17 at the bottom of the ladle 2 into the casting chamber 1. The inert gas 10 is injected as a jet 5 toward the molten metal flow 4 from an inert gas injection pipe 9 provided in the chamber 1. The molten metal is disintegrated to the fine drops 6 by the injected gas and the fine drops fall onto the base body 7 provided in the chamber 1, thereby solidifying and depositing thereon and forming the ingot. The ingot has the fine crystal structure and since the ingot solidifies quickly, the segregation of the components, more particularly, the machinability-improving element, etc. is decreased.