In the current work, the morphological evolution and mechanical properties of the
solidification structures of stirred ZA-12 zinc alloy has been investigated. The alloy was mechanically stirred in the solidification range. During stirring, the solid/liquid ratio inside the molten slurry was 50/50. The effect of shearing intensity and shearing time on the structure and mechanical characteristics of the alloy was evaluated. The results showed that both shear intensity-time combination have significant influence on the primary particles morphology. It has been showed that low shearing intensity produces coarse solidification structure while high shearing intensity produces fine non-denderitic solidification structure. Increasing the shearing time above a critical value causes the primary particles to agglomerate and form a rosette like structure. Rheocast alloys with fine structure exhibited better mechanical properties when compared with alloys having other denderitic structure or rosette structure.
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