Robert G Walley

US Patent:

40309460, Jun 21, 1977

Filed:

Apr 13, 1976

Appl. No.:

5/676508

Inventors:

Donald R. Muzyka - Reinholds PA
Robert F. Walley - Shoemakersville PA

Assignee:

Carpenter Technology Corporation - Reading PA

International Classification:

B22F 104

US Classification:

148 115P

Abstract:

The process prevents prior powder particle boundary delineation by providing one or more surfactant elements which prevent nucleation of carbides at the particle surfaces with the result that carbide precipitation occurs within the powder particles rather than predominantly at the particle surfaces. In one embodiment, a small but effective amount of one or more surfactants is added to prealloyed powder before the powder is enclosed and densified at elevated temperature. In another embodiment, the surfactant is added to the melt of the prealloyed powder prior to atomization. The surfactant should be capable of forming a vapor under the conditions of hot densification, should be a strong oxide and/or sulfide former, must be a weak carbide former, should form oxides and/or sulfides which will not nucleate carbides of other elements, and which, if present in the article made from the powder, will not objectionably affect the desired properties. Useful surfactants include magnesium, barium, calcium, cerium, lanthanum, lithium, neodymium, praseodymium, yttrium, and misch metal.

Address:

2010 10 St, Pascagoula, MS 39567

VIN:

1FMYU02Z77KB97505

Make:

FORD

Model:

ESCAPE

Year:

2007