Effect of Stirring Speed and Flow Pattern on the Microstructure of a Rheocast Al-Mg Alloy

Authors

  • P. Melali
  • P. Ashtijoo
  • B. Niroumand

Keywords:

Semi-solid alloys, Non-dendritic microstructure, Baffle, Stirring speed.

Abstract

The effect of stirring speed and the flow pattern inside a processing crucible were examined in this study. This investigation was performed on the microstructure of mechanically stirred Al-8% Mg. Results reveal that by increasing the stirring speed, morphology of primary particles becomes finer and more spherical. By using baffles, the flow pattern inside the crucible changes. This change causes the melt to accelerate along the crucible wall and producing the finer structure, more spherical and nondendritic. the model, named as nucleation and separation from the wall, posses the ability to explain the microstructure evolution in semi solid fabricated slurry. It must be mentioned that the other model named "fragmentation-agglomeration’’ cannot explain the changes in microstructure by using baffles.

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Published

2015-03-31

How to Cite

Melali, P., P. Ashtijoo, and B. Niroumand. 2015. “Effect of Stirring Speed and Flow Pattern on the Microstructure of a Rheocast Al-Mg Alloy”. Metallurgical and Materials Engineering 21 (1):35-44. https://metall-mater-eng.com/index.php/home/article/view/131.

Issue

Vol. 21 No. 1 (2015)

Section

Articles - archived

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