ESTIMATION OF THE COOLING RATE IN 3 mm SUCTION-CAST RODS BASED ON THE MICROSTRUCTURAL FEATURES
DOI:
https://doi.org/10.7494/mafe.2013.39.2.7Keywords:
rate, cellular solidification, eutectic, lamellar spacingAbstract
One of the factors influencing possibly of bulk metallic glass fomation is cooling rate attainable in the casting process. The evaluation of the cooling rate of the suction-cast 3 mm rods is presented based on the measurements of the cellular spacing in the Fe-25Ni and lamellar spacing in the Cu-33 Al alloys. The estimated cooling rates are higher close to the rod surface than in the rod axis, which indicates the dominant radial heat flow. In contrast, for the Al-33Cu alloy higher cooling rates were evaluated in the rod axis than close to the surface due to the concave perturbation of the solidification front during eutectic transformation. Based on the results obtained for the Fe-25Ni alloy, it is concluded, that the cooling rate for the suction-cast 3 mm rod is not lower than 228 Ks-1.Downloads
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