摘要
通过相场模型模拟纳米尺度晶粒生长演变过程,寻求导致晶粒异常长大的影响因素,探讨获得在纳米多晶结构AZ31镁合金中产生少量分散的大晶粒的理想混晶显微组织形成的可能性。模拟结果显示,有三个因素可以控制纳米结构中的晶粒异常长大:储存能、界面能和界面能动性。如果局域应变储能低于基体储能的1.60倍,或局域界面能高于基体的0.76倍,或局域界面能动性低于基体的3倍,则没有异常长大的晶粒出现。模拟得出,适当引入少数特定的初始纳米晶粒,可以实现预想的理想混晶组织。
Using phase field model to simulate nano-sized grains growth, the present study is to find the controlling factors for abnormal grain growth and to explore the possibility to form an ideal mixed grain structure in AZ31 Mg nanoalloy. In that mixed structure a few of relatively large grain are populated within nano polycrystalline matrix. The simulating results indicate that three factors, restored energy, interface energy and interface mobility, may control the abnormal grain growth within the nanostructure. As the local restored energy ik 1.6 times as much as that of the matrix, the local interface energy is 0.76 times as much as that of the matrix or the local interface mobility is 3 times as much as that of the matrix, no abnormal grain growth takes place. Therefore, an ideal mixed grain structure may be designed by introducing a small number of specific grains in original nanostructure by means of varying local model parameters to define higher restored energy, lower interface energy, or higher interface mobility.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2013年第5期682-686,681,共6页
Journal of Materials Science and Engineering
基金
国家自然科学基金资助项目(51171040
国家高技术研究发展计划资助项目(2013AA031601)
关键词
相场模型
镁合金
纳米结构
异常长大
phase field model l magnesium alloy nanostructure abnormal grain growth
