PURPOSE: To drastically improve efficiency in vaporizing raw metal by irradiating the plural bodies impregnated with molten metal alternately with the electron beam emitted from an electron beam generator.

CONSTITUTION: A vaporizing crucible 12 contg. raw metal 13 and an electron beam generator 14 for emitting an electron beam for heating and vaporizing the raw metal 13 are placed in a vacuum vessel 11. Plural porous bodies 21 and 22 to be impregnated with the molten metal are set in the crucible 12, and the bodies 21 and 22 are alternately irradiated with the electron beam emitted from the generator 14. Consequently, the amt. of the metal to be vaporized is stably secured, and efficiency in vaporizing raw metal is improved.