• 한국결정성장학회지
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• 제18권3호
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• pp.122-124
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• 2008

The partial phase diagram of $NaNO_3$-NaCl system was investigated and the eutectic temperature was determined as $294.5^{\circ}C$. A typical rod eutectics of $NaNO_3$-4.56 wt%NaCl was directionally solidified. The results of interrod spacing, ${\lambda}_E$ as a function of growth velocity, V, were. obtained as ${\lambda}_E\;V^{0.39}\;=\;5.26$ (temperature gradient, $G_l\;=\;21.4^{\circ}C/mm$) and ${\lambda}_E\;V^{0.32}\;=\;5.45$ ($G_l\;=\;3.9^{\circ}C/mm$) and the exponent numbers of growth velocity were smaller than the theoretical value, 1/2. The sample rotation applied during directional solidification made the interrod spacing decrease slightly.

• 한국주조공학회지
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• 제29권1호
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• pp.27-32
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• 2009

The microstructure of Al-7Si-0.4Mg-1Fe alloy mainly consists of aluminum dendrites, Al-Si eutectics, and $Al_5FeSi$ needles. When Mn was added to the alloy, the substantial amount of $Al_5FeSi$ phase was changed into Al(Mn,Fe)Si, however the needle-like morphology was almost unchanged. Combined additions of Cr or Sr with Mn to the base alloy resulted in rod-like Al(Mn, Fe,Si)Si phase. The tensile properties of as-cast alloys were enhanced by the Mn addition, especially when it was added with Sr. The tensile properties after T6 heat treatment was a little improved with 0.7%Mn addition, but Cr or Sr additions with Mn didn't show any positive effect on the properties of heat-treated alloys.