R. Hattenhauer et P. Haasen, THE DECOMPOSITION KINETICS OF CU-1 AT.PERCENT-CO AT 823 K, STUDIED BYBRIGHT-FIELD ZONE-AXIS-INCIDENCE TRANSMISSION ELECTRON-MICROSCOPY, Philosophical magazine. A. Physics of condensed matter. Defects and mechanical properties, 68(6), 1993, pp. 1195-1213
The homogeneous decomposition of a Co-1 at.% Co alloy at 823 K has bee
n investigated by bright-field-zone-axis-incidence transmission electr
on microscopy. The new method allows detection of Co precipitates with
radii r greater than or equal to 1 nm, independent of their position
in the foil, and the contrast of the particles is straightforwardly re
lated to their real dimension. So we were able to measure the particle
density N-v, the mean radius (r) over bar, the distribution function
f(r) of the radii and the pair correlation function PCF (R) of the par
ticle spacings R with high accuracy. The data have been compared with
the predictions of a modified Langer-Schwartz theory. Best corresponde
nce is obtained with a value of 240 mJ m(-2) for the interfacial energ
y per unit area of Cu-Co. The spacings R of the particles showed no si
gnificant regularity as expected from an initial spinodal-like precurs
or fluctuation of the Co concentration.