THE KINETICS OF TWEED-PATTERN FORMATION IN CUNIFE

Authors
Citation
O. Lyon et Jp. Simon, THE KINETICS OF TWEED-PATTERN FORMATION IN CUNIFE, Journal of physics. Condensed matter, 6(9), 1994, pp. 1627-1636
Citations number
10
Categorie Soggetti
Physics, Condensed Matter
ISSN journal
09538984
Volume
6
Issue
9
Year of publication
1994
Pages
1627 - 1636
Database
ISI
SICI code
0953-8984(1994)6:9<1627:TKOTFI>2.0.ZU;2-I
Abstract
The morphology of the tweed pattern during phase separation of CuNiFe single crystals has been followed by two-dimensional small-angle scatt ering (2D SAS), taking advantage of the x-ray constant enhancement by anomalous scattering. The 2D [100] intensity maps have maxima with a fourfold symmetry and can be quantitatively described by three familie s of independent rows of (100) platelets alternatively enriched in Cu and in NiFe. Three length scales are defined: the mean platelet thickn ess lambda/2 along the pile-up, its thickness distribution deltalambda , and its diameter D. Their kinetics are lambda is-proportional-to tau -0.2, deltalambda is-proportional-to t-0.27, and D is-proportional-to t-0.4 respectively. These three length scales are thus independent: in this tweed-pattern coarsening, there is no global scaling due to the increase of the anisotropy and to the increase of the regularity in th e pile-up.