The effect of Sc and Zr on the fluidity of A357 alloy was investigated using spiral fluidity resin sand molds. The results showed that the order of the fluidity was A357+Zr > A357+Sc > A357 > A357+Zr+Sc. The T_DCP and the solidification temperature range were also discussed. With Sc and Zr addition, the T_DCP and the solidification temperature range of the alloy were changed, which led to the changes of the fluidity. The order of T_DCP was A357+Zr < A357+Sc < A357 < A357+Zr+Sc and the order of the solidification temperature range was A357+Zr < A357+Sc < A357 < A357+Zr +Sc. What’s more, △T₂ (△T₂=T_P-T_DCP, T_P was pouring temperature) and △T₁ (△T₁=T_N-T_DCP, T_N was α-Al nucleation temperature) were compared, and △T₂ was better suited for fluidity investigation than △T₁.

用螺旋流动性树脂砂模研究了Sc和Zr对A357合金流动性的影响。结果表明，流动性的顺序为A357 + Zr> A357 + Sc> A357> A357 + Zr + Sc。还讨论了T _DCP和凝固温度范围。添加Sc和Zr会改变合金的T _DCP和凝固温度范围，从而导致流动性的变化。T _DCP的顺序为A357 + Zr <A357 + Sc <A357 <A357 + Zr + Sc，凝固温度范围的顺序为A357 + Zr <A357 + Sc <A357 <A357 + Zr + Sc。而且，△T ₂（△T ₂＝ T _P -T _DCP，T _P被浇注温度）和△Ť ₁（△Ť ₁ = T _Ñ -T _DCP，T _Ñ是α-Al系成核温度）进行比较，和△Ť ₂中更好地适合于比△Ť流动性调查₁。