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应用铸件在凝固时的倾出方法观察了工业纯铝试样在低过热度浇注时晶区的形成过程。结果表明，铸件激冷晶区是在凝固界面对密度很大的游离晶连续、大量捕获时形成的。铸件底部粒状堆积晶区是在游离晶沉降堆积后，因凝固层的增长速度小于游离晶的堆积速度，凝固在紧密堆积的游离晶间隙中进行而形成的。结果还表明，铸件柱状晶区的形成与生长并不要求高的温度梯度。
The pouring out method of castings during solidification was used to observe the formation of crystalline regions in the industrial pure aluminum samples during the pouring with low superheat. The results show that the chilled crystal region of the casting is formed at the solidification interface for continuous and bulk capture of large density free crystals. The grain-filled grain boundary zone at the bottom of the casting is formed after the deposition of free crystals, due to the growth rate of the solidified layer being less than the deposition rate of free crystals, and solidification in the closely packed free-standing interstitial spaces. The results also show that the formation and growth of the columnar zone do not require high temperature gradients.