Influence of Rapid Shear-Rate Changes on Microstructure Formation during Semi-Solid Processing

Abstract:

The solidification behavior of the semi-solid slurry with rapid shear-rate changes was investigated by using succinonitrile-5at.%water transparent alloy and Sn-15wt.%Pb alloy on a self-made apparatus. The results showed that the rapid changes of shear-rate improved the nucleation and promoted the globular growth of solidification microstructure in the stirred melt. The increase of shear-rate was in favor of promoting the grain growth with globular shape to a certain extent, however, when the shear-rate was beyond a critical value, the further increase of the shear-rate will lead the disappearance of the globular crystals. Thus, the microstructure of semi-solid processing could be refined by a controlled stirring process.

• Periodical: Solid State Phenomena (Volumes 116-117)
• Pages: 155-158
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.116-117.155
• Online since: October 2006
• Authors: Xin Lin, Tao Li, Wei Dong Huang
• Keywords: Microstructure, Semi-Solid Processing, Shear

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