Abstract Molten metal, particularly molten steel, is atomized by directing an atomizing fluid stream against a falling stream of the molten metal. The atomized molten metal is directed against an impingement plate which is positioned relatively close to the point of intersection of the metal stream and fluid stream to obtain a maximum of relatively fine irregular particles and which is positioned relatively far from the point of intersection to obtain the maximum of generally spherical particles. It is preferred to direct a fluid jet downwardly and inwardly into the falling stream from only one side of the falling stream. My preferred apparatus includes a closed tank having an annealing chamber at its bottom. By using a non-oxidizing gas as the atomizing fluid, the pellets produced can be used for powder metallurgical uses without further processing.
Apparatus for producing metal powder which comprises an atomizing tank, containing means for providing a falling stream of molten metal, an impingement plate near said falling stream, means providing at least one fluid jet directed downwardly and inwardly into said falling stream to atomize said molten metal into small particles and to direct said particles against said impingement plate, and an annealing chamber at the bottom of said tank which includes a plurality of vertically spaced trays having openings therethrough, a rotatable shaft extending through said trays, a scraper mounted on said shaft above each tray, and means for rotating said shaft.
Claim 2
Dependent Claim
102 words
Apparatus for producing metal powder which comprises an atomizing tank, containing means for providing a falling stream of molten metal, an impingement plate near said falling stream, means providing at least one fluid jet directed downwardly and inwardly into said falling stream to atomize said molten metal into small particles and to direct said particles against said impingement plate, and an annealing chamber at the bottom of said tank which includes a plurality of vertically spaced trays having openings therethrough, a rotatable shaft extending through said trays, a scraper mounted on said shaft above each tray, and means for rotating said shaft.
Claim 3
Dependent Claim
21 words
Apparatus according to claim 1 in which all the fluid jets are located within an arc of less than 180* .
Claim 4
Dependent Claim
29 words
Apparatus according to claim 2 including a slow cooling zone in said annealing chamber below the bottom tray, and means for introducing a non-oxidizing gas into said cooling zone.
Claim 5
Dependent Claim
19 words
Apparatus according to claim 3 including an enclosed screw conveyor connected to the lower end of said cooling zone.
Claim 6
Dependent Claim
28 words
Apparatus according to claim 4 including means providing heat to the top part of the annealing chamber and means for cooling said cooling zone and said screw conveyor.