龙永强,刘平,刘勇,贾淑果,田保红

• 1:河南科技大学材料科学与工程学院
• 2:上海交通大学材料科学与工程学院
• 3:上海理工大学机械学院

摘要(Abstract)：

基于相场方法,模拟研究了Cu-20和40at%Ag合金在等温时效过程中相分解与微观组织的演变。系统自由能中耦合了体化学能、浓度梯度能和共格错配应变能,化学自由能是直接利用相图热力学数据计算得到的,因此,计算的微结构变化与真实合金系统是相对应的。通过模拟,获得了合金的形态和浓度分布随时间、温度和组分的变化规律。模拟结果表明,对称合金(Cu-40at%Ag)分解和粗化的速度均高于相应的非对称合金,其相分离的早期阶段形成规则的、相互连接的微观形态。在Cu-20at%Ag合金中,沉淀相Ag经历了调幅分解和粗化过程,其形态呈立方状,沿[110]方向排列。

关键词(KeyWords)： 相场模型;调幅分解;微结构演变;形态

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 龙永强,刘平,刘勇,贾淑果,田保红

DOI: 10.13289/j.issn.1009-6264.2010.09.010

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