Effect of Ca addition on solidification microstructure of hypoeutectic Al-Si casting alloys
The effect of Ca addition on the solidification microstructure of hypoeutectic Al-Si casting alloys was investigated using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) methods with particular attention focused on the change of morphologies of primary α-Al and eute...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Foundry Journal Agency
2019-05-01
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| Series: | China Foundry |
| Subjects: | |
| Online Access: | http://ff.foundryworld.com/uploadfile/2019052848988329.pdf |
| Summary: | The effect of Ca addition on the solidification microstructure of hypoeutectic Al-Si casting alloys was
investigated using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) methods
with particular attention focused on the change of morphologies of primary α-Al and eutectic silicon. Meanwhile,
solute distribution in solid-liquid was simulated according to Scheil-Gulliver law. Results showed that primary α-Al
and eutectic silicon were refined as Ca content increased because of the variation of the solute concentration in
liquid. The addition of Ca increased the nucleation sites like Al3Ti or Al2Cu to promote the nucleation of primary
α-Al. Affected by modification effect of Ca, the shape of eutectic silicon changed from flake to fibrous structure. In
addition, coarse plate Ca-rich phases could be found along the grain boundary with high Ca content. |
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| ISSN: | 1672-6421 1672-6421 |