Accession Number : ADA185393

Title :   A Fundamental Study of P/M Processed Elevated Temperature Aluminum Alloys.

Descriptive Note : Final rept. 1 Oct 81-30 Sep 86,

Corporate Author : DREXEL UNIV PHILADELPHIA PA DEPT OF MATERIALS ENGINEERING

Personal Author(s) : Lawley, A ; Koczak, M J

PDF Url : ADA185393

Report Date : Jul 1987

Pagination or Media Count : 38

Abstract : Ambient and elevated temperature tensile and creep response, and microstructural stability of a powder processed AL-Fe-Ce alloy have been evaluated. Gas atomized Al-Fe-C was mechanically alloyed (MA) to give a volume fraction of dispersoids of about 0.23. The powder was could isostatically pressed in aluminum cans, outgassed and hot extruded to full density. Consistent with improved microstructural stability at elevated temperatures, the MA material is stronger and more creep resistant than the non-MA material. These improvements are attributed to the presence of fine scale oxides and carbides distributed uniformly throughout the structure, and which are introduced during MA; the dispersion inhibits coarsening, recovery and recrystallization. Non-MA Al-Fe-Ce is stronger than non-MA Al-Fe-Ni at all temperatures but it has limited ductility. Qualitatively, the effect of MA on Al-Fe-Ce is similar to that in Al-Fe-Ni. These results suggest that Ce alters the transformation characteristics of Al-Fe and/or that Ce diffuses more slowly that Ni in Al, in the presence of Fe.

Descriptors :   *CREEP, *POWDER METALLURGY, *ALUMINUM ALLOYS, EXTRUSION, CRACKING(FRACTURING), ALUMINUM, NICKEL, IRON, CERIUM, OXIDES, CARBIDES

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE