Accession Number:

ADA179547

Title:

Al and Mg Alloys for Aerospace Applications Using Rapid Solidification and Powder Metallurgy Processing.

Descriptive Note:

Annual rept. 15 May 86-15 May 87,

Corporate Author:

ILLINOIS UNIV AT URBANA DEPT OF METALLURGY AND MINING ENGINEERING

Personal Author(s):

Report Date:

1987-05-01

Pagination or Media Count:

13.0

Abstract:

The first section of the progress report is concerned with the development of rapidly solidified Al-8Fe-2Mo-SI alloys for elevated temperature applications. Rapidly solidified Al-8FE-2Mo alloys containing silicon in the range of 0 to 1wt pct were produced by melt spinning. In the second annual report, preliminary results of the effect of Si on the formation of the Sone A microstructure and on subsequent changes of this structure during heat-treatment were described. It was shown that addition of Si has a dramatic effect on the trasnformation behavior and microstructure of heat-treated ribbons. In contrast to the thermally unstable, multiphase precipitate distribution in the ternary Al-8FE-2Mo alloy, quarternary Si-containing alloys showed a uniform dispersion of fine cuboidalpolygonal precipitates, which displayed a remarkable resistance to coarsening. A typical TEM micrograph portraying this effect is shown in FIg 1 for a Al-8Fe-2Mo0-0.5Si alloy heat treated at 450 C for 50 hrs. To identify the nature of the precipitates, x-ray and electron diffraction were used, and these results are reported here. Keywords Molybedenum alloys Silicon aluminum alloys Iron alloys.

Subject Categories:

  • Properties of Metals and Alloys

Distribution Statement:

APPROVED FOR PUBLIC RELEASE