Method for making centrifugally cooled powders

A method for producing powder of metal or alloy material comprising:

• (a) providing a molten stream of said material;
• (b) providing a pressurized source of fluid;
• (c) providing a housing having a substantially cylindrical wall defining along a central first axis a generally cylindrical chamber having preselected radius and an inlet at a first end thereof and an outlet at a second end thereof, said cylindrical wall including means defining a plurality of passageways through said wall along respective second axes each oriented with respect to said wall along a vector having preselected mutually orthogonal components respectively along a radius of said chamber, along said first axis and tangent to said wall, said passageways spaced both circumferentially and lengthwise of said cylindrical wall;
• (d) atomizing said molten stream into molten droplets of said material;
• (e) injecting said fluid through said passageways into said chamber under pressure sufficient to generate a plurality of vaporous fluid of preselected flow rate whereby said vaporous fluid is helically swirled within said chamber and directed generally toward said second end of said chamber;
• (f) directing said molten droplets through said chamber in contact with said vaporous fluid jets whereby said droplets are swirled within said chamber toward said second end thereof and cooled to form powder of said material within said chamber;
• and
• (g) collecting said powder.