(1. 中国科学院 金属研究所，沈阳110016；
2. 华南理工大学 材料科学与工程学院，广州510640；
3. 中国科学院计算机网络信息中心，北京100190；
4. The Ohio State University, Columbus OH 43210, USA)
摘 要: 通过相场方法定量模拟不同α初始颗粒尺寸分布(包括均匀、正态、对数正态以及双态分布)对Ti-6Al-4V 合金中α相颗粒溶解动力学的影响。方法中引入KKS 模型，从而避免界面能对化学自由能的依赖。结果发现：不同α初始颗粒尺寸分布下的α体积分数随时间的变化均符合衰减规律：f=fαexp(−Ktn)，而α相体积分数及颗粒平均半径随时间的演化关系强烈依赖于α颗粒的初始尺寸分布。4种分布状态下α相的溶解速度从快到慢依次为均匀分布、正态分布、对数正态分布和双态分布。在对数正态和双态分布下，颗粒半径的演化均随时间先减小再增加，最后一直递减，而对于均匀和正态分布则随时间呈单调递减趋势。
关键字: 相场；Ti-6Al-4V合金；β相区；尺寸分布；溶解
3D phase field model
（1. Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China;
2. School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China;
3. Computer Network Information Center, Chinese Academy of Sciences, Beijing 100190, China;
4. The Ohio State University, Columbus OH 43210, USA）
Abstract:3D quantitative phase field method coupled with KKS model was applied to study the effect of initial particle size distribution (PSD) on dissolution of α phase in Ti-6Al-4V in real time and length scale. The results show that the volume fraction and average particle radius of α phase depend on the initial particle size distribution. The volume fraction of the α phase decays as f=fαexp(−Ktn). The sequence of dissolution kinetics for different distribution from fast to slow is uniform, normal, lognormal and bimodal. The average particle radius increases after an initial reduction, then decreases monotonously for log-normal and bimodal PSD, but it decreases monotonously with time for uniform and normal PSD.
Key words: phase field; Ti-6Al-4V alloy; β phase zone; particle size distribution; dissolution
