Temperature and initial composition dependence of pattern formation and dynamic behavior in phase separation under deep-quenched conditions.
Temperature and initial composition dependence of pattern formation and dynamic behavior in phase separation under deep-quenched conditions.
复制标题
深度淬火条件下相分离中图案形成和动态行为的温度和初始成分依赖性
作者：
对SCN-H2O([CH2CN]2-H2O)透明溶液的相分离进行了二维模拟，并用Minkowski泛函研究了淬火温度和初始组成对第二相花样形成和动力学行为的影响。模拟基于H模型，其中SCN-H2O溶液的摩尔自由能由CALPHAD方法得到。我们发现，组成和温度不影响磁畴增长规律中的指数，其中平均磁畴尺寸随时间的变化得到R(T)-tn。但是，它们会影响相分离中第二相的花样形成和动力学行为。温度越低，调幅分解的双连续结构越细小，形核速度越快，相分离越快，液滴越多，尺寸越小。当初始成分偏离临界值时，空间分布由双连续逐渐转变为液滴状结构。当初始组分越接近临界值时，对于调幅分解，扩散驱动生长的时间越长，液滴的平均区域尺寸越大。相反，对于形核驱动的生长，单相分离更快，液滴的平均尺寸更小。温度和初始组成影响相分离中第二相的花样形成和动力学行为。
Phase separation of SCN-H2O ([CH2CN]2–H2O) transparent solutions is simulated in two dimensions and the effects of quenching temperature and initial composition on the pattern formation and dynamic behavior of the second phase are examined via Minkowski functionals. The simulation is based on model H where the molar free energy of the SCN-H2O solution is obtained by the CALPHAD approach. We find that the composition and temperature do not affect the exponent in the domain growth law, where the average domain size with time yields R(t)–tn. However, they influence the pattern formation and dynamic behavior of the second phase in phase separation. Lower temperature leads to a finer bicontinuous structure in spinodal decomposition and promotes the nucleation rate, which accelerates the phase separation and results in more liquid droplets with smaller size. As the initial composition diverges from the critical value, the spatial patterns change gradually from bicontinuous into a droplet-like structure. When the initial composition is closer to the critical value, for spinodal decomposition, the diffusion-driven growth lasts for a longer time and the average domain size of liquid droplets is larger. For nucleation-driven growth, in contrast, the single phase separates more quickly and the average size of liquid droplets is smaller. Temperature and initial composition influence the pattern formations and dynamic behaviors of the second phase in phase separation.
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影响因子：
4
作者：
Haataja, M;Mahon, J;Léonard, F
通讯作者：
Léonard, F
影响因子：
4.4
作者：
Abyzov, Alexander S.;Schmelzer, Juern W. P.
通讯作者：
Schmelzer, Juern W. P.
影响因子：
1.8
作者：
Hansen, G;Liu, S;Hellawell, A
通讯作者：
Hellawell, A
影响因子：
8.6
作者：
Kendon, VM;Desplat, JC;Cates, ME
通讯作者：
Cates, ME
DOI：
10.1016/s0364-5916(96)00021-1
发表时间：
1996-06-01
影响因子：
2.4
作者：
Kumar, KCH;Wollants, P;Delaey, L
通讯作者：
Delaey, L