Abstract
In order to develop high strength new casting aluminum alloys, a relation between microstructure and strength in multiphase eutectic alloys was analyzed from points of view of both theoretical and experimental approaches. Initially, microstructure of multiphase eutectics was discussed.
Secondary, an Al-Ce-Ni multiphase eutectic alloy was cast and examined by compression test.
Finally, strengthening mechanism of the Al-Ce-Ni multiphase eutectic alloy was analyzed. The results obtained are as follows. Even in the conventional foundry technique the multiphase eutectic alloy has large amounts of aluminide particles being very fine because of the independently crystal nucleation. The Al-Ce-Ni multiphase eutectic alloy showed 30∼200% higher strength than commercial casting aluminum alloys. The strength consisted of strength of the aluminide particle itself, internal stress due to dislocations in Al phase and also Orowan stress increments due to the fine aluminide particles. This indicates the possibility in principal to develop new casting aluminum alloys.
