516 Prakt. Met. Sonderband 38 (2006)
time increase to 270 min as shown in Fig. 4(d), the size of the Y211 phase increased
compare to the sample in (b) and (c). The size increase of the second particles with
attrition milling time may be due to the higher stress state and high agglomeration of the
finer powder which may result in faster melt growth during process. Thi
red
Wit
effe
phe
the
tim
res
witl
of
red
Bat
RE
(c) (d)
Fig. 4: Optical micrographs of the melt-textured Y123 samples from the mixed precursor [1]
(a) as calcined, and attrition milled for (b) 30 min, (c) 150 min., and (d) 270 min.
[2]
[3]
[4]
N DS)
(a
(C) (d)
Fig. 5: High magnification micrographs of the melt-textured Y123 samples shown in Fig. 4.
a
x
Br