Porosity Prediction in Aluminum A356 Alloy Castings
نویسنده
چکیده
A comprehensive methodology that takes into account alloy solidification, shrinkage-driven interdendritic fluid flow, hydrogen precipitation, and porosity evolution has been developed for the prediction of microporosity fraction in aluminum A356 alloy castings. The mathematical models presented are implemented in a computational framework consistent with those of commercial casting codes, allowing them to be easily incorporated in commercial casting simulation software. Examples are presented for two test-plate castings of vastly differing solidification behavior. The analysis of (a) metallographic observations of the pore morphology distribution, (b) computed solid fraction distribution, and (c) computed pressure distribution during solidification is used to explain the pore fraction evolution during solidification. The predictions of porosity distribution are validated by comparison with independent experimental measurements of pore fraction in the test plate castings.
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