Prakt. Met. Sonderband 38 (2006) 71 
micro- 
d and 
5.781.9 
o—den- 
han in 
Chinese 
ructures 
10 um 
_ 100 pm __ . Zu um 
tes and 
J the 
+ 
Fig.7: Micrographs of gravity cast AG4.9S8.4 : LOM in a) and b) with o. dendrites and 
heterogeneous structures in between identified by EDX element mapping. The same area 
as b) is presented in d) by a BSE image, for which the distribution of Mg representing 
Mg,Si is given in c), that of Si in e), and that of Fe representing AlFeSi in f). 
which are identified by the element mappings in Fig.7c-f. The BSE image in Fig.7d does 
lume not show the Si eutectic, but the Mg,Si and AlFeSi inclusions solidified with it. The volume 
e-rich view of the micro-tomogram of the selected AlFeSi phases in Fig.8a shows that AlFeSi 
precipitates either as needles or as extended aerial features of high connectivity. The grey 
level distribution of central cross section of the represented volume in Fig. 8b shows the 
on treat cross sections of these AlFeSi inclusions (white) similar to the 2D views in LOM and SEM, 
ed. Fig. where AlFeSi appears always as “needles”. The 2D cuts of the chinese script Mg,Si 
AlFeSi, appear dark like in BSE images. The coral like 3D shape of the Mg,Si is depicted in the