Sumitomo Metal Industries, Inc.

Nippon Oil Company

Minoru Ichidate

Toshihiko Kubo

Masahide Umino

Isamu Karasuno

Eijiro Tamura

Yoshihisa Koiwai

Tatsuhiko Shigematsu

Toshiyuki Kawai

Kazuhiko Endo

Yohzi Tozawa

Chitose Shiotani

Sadao Yonehara

A process for producing cold-bonded or non-fired iron ore which introduced as a charge into a blast furnace. The iron ore, which contains 10 to 70% of particles having a diameter ranging from 1 to 10 mm, is molded into a block, preferably by a pressure-molding method, a shock-molding method or a packing-molding method with vibrations. The block is then cured or hardened. This hardened block is crushed to have a predetermined shape. An additive such as CaO, Al.sub.2 O.sub.3, or MgO may be added to the iron ore to adjust the basicity as a whole to 0.8 to 2.0. Moreover, the molding step is conducted so that the product may have a void volume equal to or less than 25%.

Process for producing cold-bonded iron ore for use in a blast furnace

A metal powder of improved quality is obtained by causing molten metal held in a vessel to flow out in a smooth stream through an outlet formed at the bottom of the vessel, throwing the jet of an atomizing medium consisting of nonpolar solvents such as mineral oils, or animal and vegetable oils against the stream of molten metal thereby atomizing the molten metal, separating and recovering the produced metal powder and the used atomizing medium by means of a fluidized bed furnace, and if necessary subjecting the metal powder to decarburization and softening anneal. In this production, the molten metal, the path for the flow of the molten metal, and the produced metal powder are substantially insulated from the atmospheric air.

Apparatus for production of metal powder

A process for producing alloy steel powder, particularly, low-oxygen, low-carbon alloy steel powder is disclosed. The process comprises: preparing molten steel which contains at least one easily oxidizable element selected from the group consisting of chromium, manganese, vanadium, niobium, boron and silicon; atomizing said molten steel by means of an atomizing agent containing a non-oxidizing medium to provide as-atomized alloy steel powder containing 0.2% by weight or less of oxygen and 0.1% by weight or more of carbon; decarburizing the resulting powder by maintaining it in an atmosphere containing at least H.sub.2 and H.sub.2 O gases under specified conditions; and cooling the thus decarburized alloy steel powder to room temperature in an inert or reducing atmosphere.

Process for producing alloy steel powder

An oil-atomized low-alloy steel powder having improved compressibility, compactibility and hardenability is disclosed. The steel powder has the chemical composition: C: no greater than 0.02%, Mn: 0.3-2.0%, oxygen: no greater than 0.10%, one or more of Cr: 0.1-2.0%, Mo: 0.05-1.0%, Ni: 0.1-2.0%, Cu: 0.2-2.0%, V: 0.03-0.5% and Nb: 0.05-0.5%, and the balance substantially iron.

Oil-atomized low-alloy steel powder

Metal powder having low oxygen and carbon contents and suitable for powder metallurgy may be obtained by using, as an atomizing medium, a special composition containing an alcohol having 1-4 carbon atoms and water as its essential components when impinging the atomizing medium against a molten metal in a state isolated from the ambient air to produce the metal powder.

Process for producing metal powder

Method and apparatus for production of metal powder

Growing community of inventors

Amagasaki, Japan

Minoru Ichidate