Abstract: The inversion casting technics of producing three-ply Al-Mn/Al-Si composite strap used in automobile radiator was studied. The physical processes of inversion casting, including the fluxsupporting reacting and volatilizing at high temperature, the melting and solidification when the elements of solid and liquid fresh alloys meet with each other, the mutual diffusion of elements in solid and liquid, the crystallization and forming of metallurgical combination and the following rolling process, were analyzed. At the same time, the composite mechanism of this technique was also discussed.

Key words: composite aluminum alloy; inversion casting; automobile radiator; composite mechanism