(1. 湘潭大學 機械工程學院，湘潭 411105；
2. 中南大學 材料科學與工程學院，長沙 410083)
摘 要: 采用金屬型鑄造制備在720 ℃和960 ℃熔煉后正常凝固的2618鋁合金；采用液淬法制備在720 ℃和960 ℃下分別保溫20 min和1 h后快速凝固的Al-2.25Cu-1.6Mg-1.8Fe-1.89Ni合金；對鋁合金熔體中Al3Fe相及Al9FeNi相的溶解動力學進行分析。結果表明：在960 ℃下對2618鋁合金熔體進行一定時間的高溫過熱處理，可以消除中間合金中的粗大Al3Fe相和回爐料中粗大Al9FeNi相的組織遺傳現象，并在鋁合金的鑄錠組織獲得均勻細小的Al9FeNi相。
關鍵字: 2168鋁合金；熔體處理；溶解動力學；快速凝固；組織遺傳性
phases in aluminum alloy melt
（1. School of Mechanical Engineering, Xiangtan University,
Xiangtan 411105, China;
2. School of Materials Science and Engineering, Central South University,
Changsha 410083, China）
Abstract:The 2618 Al alloy with as-cast solidifying microstructure was obtained through pouring the melt into permanent mold, which was overheated at 720 and 960 ℃, respectively. At the same time, the melt of Al-2.25Cu-1.6Mg- 1.8Fe-1.89Ni alloy with rapidly solidified microstructure was obtained, which was overheated at 720 and 960 ℃ for 20 and 1 h， respectively. The solution kinetic of Al3Fe and Al9FeNi phase in aluminum alloy melt was analyzed. The results show that the structural heredity of coarse Al3Fe phase in master alloy and coarse Al9FeNi phase in returns can be eliminated by overheating the melt of alloy 2618 at 960 ℃ for a definite time, which results in the formation of fine and uniform Al9FeNi phase.
Key words: 2618 Al alloy; melt-treatment; solution kinetic; rapid solidification; structural heredity
