摘要
通过实验及计算测得准确的固-液界面能,对于理解并掌握该合金凝固及形核的过程具有很大的帮助.用分子动力学方法对铝的均质形核过冷度进行了模拟,运用模拟得到的均质形核过冷度计算得到对应固-液界面能的值.进一步得到了Al在熔点温度下其理想光滑固-液界面的固-液界面能σ0,通过σ0对铝在不同温度下及Al-Mg在共晶温度和成分点的固-液界面能进行了预测.计算结果发现:不同均质形核过冷度计算得到的Al在熔点温度下其理想光滑固-液界面的固-液界面能σ0分别为0.199 8,0.199 9,0.199 8J/m2;由σ0对Al-Mg合金固-液界面能的预测的结果及凹槽法所得到的实验值分别为0.155 1J/m2和0.149 2±0.019 4J/m2,其误差小于4%.
Knowing the accurate solid-liquid interracial energy is of great help for understanding and grasping procedure of the alloy solidification and nucleation. The homogeneous nucleation undercoolings of aluminum were simulated by using molecular dynamics method and the solid-liquid interface energy was calculated according to the simulated homogeneous nucleation undercoolings. Based on that, the solid-liquid interface energy of aluminum, in the perfectly smooth solid-liquid interface, at the melting point was obtained. Then the solid-liquid interface energies of aluminum at different temperatures and those of aluminum- magnesium in the eutectic composition and at the eutectic temperature were predicted. It is found .. With different homogeneous nucleation undercoolings, the predicted solid-liquid interface energies of aluminum, in the perfectly smooth solid-liquid interface, at the melting point are 0. 199 8 J/m2 ,0. 199 9 J/m2 and 0. 199 8 J/m2 respectively Moreover,the predicted and the experimental results of solid-liquid interface energy of aluminum-magnesium alloy are 0. 155 1 J/m2 and 0. 149 2 ±0. 019 4 J/m2 ,the error between them is less than 4%.
出处
《西安工业大学学报》
CAS
2012年第6期476-481,共6页
Journal of Xi’an Technological University
基金
国家973项目(2011CB610403)
国家自然科学基金(51071115
50671075
51171136)
关键词
分子动力学模拟
均质形核过冷度
固-液界面能
铝镁合金
molecular dynamics simulatiomhomogeneous nucleation undercooling solicl-liquid interface energy aluminum-magnesium alloy
