Eui W Lee

US Patent:

6436208, Aug 20, 2002

Filed:

Apr 19, 2001

Appl. No.:

09/837900

Inventors:

Rabindra Mahapatra - Port Tobacco MD
Eui W. Lee - Maple Glen PA
Jeffrey Waldman - Huntington Valley PA
John H. Perepezko - Madison WI

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C22C 1400

US Classification:

148562, 148404, 148421, 420418, 117 41

Abstract:

A process of preparing aligned, in-situ, two-phase single crystal alloys of titanium, aluminum and niobium which comprises growing the alloys at rates of about 3. 0 mm. to about 6. 0 mm. per hour by rotating a seed rod alloy consisting essentially of Ti-43 to 45 Al-10 to 12 Nb+0. 5 Si, in atomic percent, at about 7. 75 to 8. 25 RPM while in contact with a rotating feed rod alloy consisting essentially of Ti-43 to 45 Al-10 to 12 Nb, in atomic-percent, rotating at about 5. 75 to 6. 25 RPM in an atmosphere of substantially pure argon at melt temperatures ranging from about 1650Â C. to 1750Â C. to obtain two-phase single crystal alloys of Ti-43 to 45Al-10 to 12 Nb characterized as having improved ductility, excellent oxidation resistance, and high-temperature creep strength. These alloys are particularly useful for manufacturing high-temperature material components for internal combustion engines, gas turbines, and advanced aircraft engines.

US Patent:

51713748, Dec 15, 1992

Filed:

Nov 28, 1988

Appl. No.:

7/276748

Inventors:

Nack J. Kim - Florham Park NJ
Eui W. Lee - Warminster PA

Assignee:

Allied-Signal Inc. - Morris Township, Morris County NJ

International Classification:

C22F 104

US Classification:

148698

Abstract:

A rapidly solidified aluminum base lithium containing alloy is subjected to at least one overaging treatment and a plurality of rolling passes. Upon completion of the process, the alloy is comprised of grains having an ultrafine grain size. A predominant number of the grains have grain boundaries pinned by the precipitation of Al. sub. 3 Zr phase. The alloy has an elongation greater than 500% at temperature above about 500. degree. C. and a strain rate above about 4. times. 10. sup. -2 /s.