【摘 要】
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Porosity formation during solidification of aluminum-based alloys,due to hydrogen gas and alloy shrink-age,has been a major issue adversely affecting the perfor
【机 构】
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Department of Materials Science and Engineering,The Ohio State University,Columbus,OH 43210,USA;Depa
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Porosity formation during solidification of aluminum-based alloys,due to hydrogen gas and alloy shrink-age,has been a major issue adversely affecting the performance of solidification products such as castings,welds or additively manufactured components.A three-dimensional cellular automaton (CA) model has been developed,for the first time,to couple the predictions of hydrogen-induced gas porosity and shrink-age porosity during solidification microstructure evolution of a binary Al-Si alloy.The CA simulation results are validated under various cooling rates by porosity measurements in an experimental wedge die casting using X-ray micro computed tomography (XMCT) technique.This validated porosity moel pro-vides a critical link in integrated computation materials engineering (ICME) design and manufacturing of solidification products.
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