含共格畸变的立方合金粗化机制的原子层面计算机模拟研究(英文)  

Atomic-Scale Computer Simulation for the Coarsening Mechanism of the Cubic Alloy Including Coherent Strain Energy

作　　者：卢艳丽[1] 陈铮[1] 李永胜[1] 王永欣[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》2006年第11期1686-1690,共5页Rare Metal Materials and Engineering

基　　金：Supported by the National Natural Science Fundation of China (50071046) and High Technology Research and Development Program of China (2002AA331051)

摘　　要：基于微观相场动力学模型,编制了包含共格畸变能的二元立方合金沉淀过程微观组织演化的计算机模拟程序,开展了不同共格畸变能作用下,溶质浓度为20at%的二元镍基合金的粗化机制的计算机模拟。研究发现:共格畸变能为零时,粗化遵循LSW机制,仅仅由颗粒的尺寸大小决定;随着共格畸变能的增大,粗化过程遵循混合机制,由沉淀颗粒的大小和位向(颗粒间的相对位置)共同决定;当共格畸变增大到一定程度时,粗化过程纯粹由颗粒间的位向决定,处于弹性“软”方向上的颗粒优先长大,而处于弹性“软”方向外的颗粒将消失掉。The program of simulation for the evolution of microstructure during the precipitated process of binary cubic alloy including coherent strain energy is carried out based on the microscopic phase-field kinetic model. The precipitate＇s coarsening mechanism in Ni-based alloy with 20% solute （atomic fraction） under different coherent strain energies are studied. The results show that when the coherent strain energy is neglected, coarsening process follows LSW mechanism, which is decided only by the size of the precipitate; with increasing of coherent strain energy, coarsening process follows the mixed mechanism which is decided by both the size and orientation （mutual position） of the precipitates. When the coherent strain energy increases to some extent, coarsening process is decided only by the orientation of the particles, which grow up and coarsen preferentially along the elastically soft directions （〈01〉directions） and the particles lying out of the soft directions disappear.

关 键 词：镍基合金 粗化机制 共格畸变能 计算机模拟 

分 类 号：TG111[金属学及工艺—物理冶金]