Nkk Corporation

Nippon Kokan Kabushiki Kaisha

Yoshio Takagi

Hiroaki Nishio

Tsuneo Miyashita

Takeshi Kawashima

Kazuya Yabuta

A method of casting a powdered material. A slurry is formed by dispersing metal powder or ceramic powder into a dispersing medium mainly consisting of a substance extractable by a liquid or supercritical carbon dioxide and having a melting point between 0.degree. C. and 100.degree. C., and the slurry is poured into a liquid non-absorbing mold where the slurry is cooled to freeze and solidify into a molding. The main constituent of the dispersing medium in the molding is extracted and removed by the liquid or supercritical carbon dioxide.

Method of casting powder materials

The invention is concerned with the method of compression molding a metallic or ceramic powders. The method includes the step of maintaining a negative pressure within a first mold of noncompactable powders for intimately contacting on its inner surface a pouch-like member of thin-walled resilient material for producing a second mold, and the step of compactly charging starting powders into the second mold and exhausting air from and sealing the second mold, taking out a pre-molded body of the metallis or ceramic powders together with the second mold and the step of processing the pre-molded body by a cold or hot isostatic press.

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Yokohama, Japan

Yoshio Takagi