TY - JOUR
T1 - Influence of gravity on the microstructure of directionally solidified Ag-Si eutectic alloy
AU - Aoi, Ichiro
AU - Yoshida, Makoto
AU - Fukunaga, Hideharu
AU - Nakae, Hideo
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1999/1
Y1 - 1999/1
N2 - In order to study the influence of gravity on the eutectic growth of Ag-Si and Al-Si alloys, both the downward (direction of gravity) and upward (opposite to direction of gravity) unidirectional solidifications were carried out. In the case of the downward U.D.S., the molten metal is confined between the crucible and solid. This inevitably produces the shrinkage cavity at the solid/liquid interface during solidification. In this study, the zone-melting technique was used to avoid this cavity formation. The results of this study were as follows: (1) In the case of the downward U.D.S. of the Ag-Si alloy, the eutectic silicon phase grew discontinuously and dispersed in the α-Ag phase with a diameter of several micrometers. This is caused by the large difference in specific density between silver and the silicon phase. On the other hand, in the case of the upward U.D.S., the silicon phase grew continuously and its morphology showed the typical faceted/non-faceted eutectic. (2) The eutectic silicon phase of the Al-Si alloy grew continuously regardless of growth direction. There was no morphological difference between the upward and downward U.D.S. specimens.
AB - In order to study the influence of gravity on the eutectic growth of Ag-Si and Al-Si alloys, both the downward (direction of gravity) and upward (opposite to direction of gravity) unidirectional solidifications were carried out. In the case of the downward U.D.S., the molten metal is confined between the crucible and solid. This inevitably produces the shrinkage cavity at the solid/liquid interface during solidification. In this study, the zone-melting technique was used to avoid this cavity formation. The results of this study were as follows: (1) In the case of the downward U.D.S. of the Ag-Si alloy, the eutectic silicon phase grew discontinuously and dispersed in the α-Ag phase with a diameter of several micrometers. This is caused by the large difference in specific density between silver and the silicon phase. On the other hand, in the case of the upward U.D.S., the silicon phase grew continuously and its morphology showed the typical faceted/non-faceted eutectic. (2) The eutectic silicon phase of the Al-Si alloy grew continuously regardless of growth direction. There was no morphological difference between the upward and downward U.D.S. specimens.
KW - Aluminum-silicon alloy
KW - Eutectic
KW - Gravity
KW - Silver-silicon alloy
KW - Solidification
UR - http://www.scopus.com/inward/record.url?scp=0032624847&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032624847&partnerID=8YFLogxK
U2 - 10.2320/matertrans1989.40.27
DO - 10.2320/matertrans1989.40.27
M3 - Article
AN - SCOPUS:0032624847
VL - 40
SP - 27
EP - 33
JO - Materials Transactions
JF - Materials Transactions
SN - 1345-9678
IS - 1
ER -