Accession Number:

ADP012242

Title:

What Xe Nanocrystals in Al Can Teach Us in Materials Science

Descriptive Note:

Corporate Author:

NATIONAL INST FOR MATERIALS SCIENCE TSUKUBA (JAPAN)

Report Date:

2001-11-01

Pagination or Media Count:

6.0

Abstract:

Noble gases are generally very insoluble in solids. For example, Xe implanted into Al at 300 K forms a fine dispersion of crystalline precipitates and, at large enough fluence. fluid precipitates, both of which are stabilized, relative to the gas phase, by the Laplace pressure due to precipitatematrix interface tensions. High resolution electron microscopy has been performed to determine the largest Xe nanocrystalline precipitate in local equilibrium with fluid Xe precipitates within the Al matrix. From the shape and size of the largest crystal and the Laplace pressure associated with its interface, we show that the interface tensions can he derived by setting the Laplace pressure equal to the pressure for solidfluid Xe equilibrium derived from bulk Xe compression isotherms at the temperature of equilibration and observation. The XeAl interface tensions thus derived are in the range of accepted values of surface tensions for the Al matrix. Furthermore, it is suggested that this same technique may be employed to estimate unknown surface tensions of a solid matrix from the size and shape of maximal nanocrystals of a noble gas element, which have been equilibrated in that matrix at the temperature of observation.

Subject Categories:

  • Inorganic Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE