液态锌凝固过程中的分子动力学模拟研究

摘要

The cooling rate has great influence on the microstructure and performance during the hot-dip process of zinc on the surface of steel. Molecular dynamics simulation based on the Morse potential was carried out to investigate the rapid solidification of Zn. Radial distribution function, energy analysis, Voronoi polyhedral structure analysis were used to analyze the microstructure evolution in the solidification process. The results indicate that amorphous structure forms when the cooling rate exceeds 2.5× 1012K/s; crystal forms when the cooling rate is less than 7.0× 1011 K/s.The crystallization temperature increases with cooling rate decreasing and amorphous transition temperature increases with cooling rate decreasing.%采用Morse势函数,用分子动力学方法研究了冷却速度对液态金属锌凝固过程微观结构的影响.利用径向分布函数、能量分析、Voronoi多面体结构分析等方法分析了凝固过程中的微观结构演变特征.结果表明,冷却速率大于2.5×1012 K/s时,得到非晶态结构;冷却速率小于7.0×10 11K/s时,将发生结晶.同时发现,在结晶时冷却速率越慢,结晶转变温度Tc越高；发生非晶转变时,冷却速度越快,其非晶转变温度Tg越高.