晶格常数变化与有序无序转变类型的关系  

Relationship Between Lattice Parameter Variation and Order-Disorder Transformation Type

作　　者：王建民[1] 倪晓东[2] 陈国良[3] 

机构地区：[1]华北水利水电学院,邯郸056021 [2]北京科技大学材料科学与工程学院物理系,北京100083 [3]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《北京科技大学学报》2003年第3期234-236,共3页Journal of University of Science and Technology Beijing

基　　金：国家自然科学基金资助项目(No.59895151)

摘　　要：利用EAM势计算了Ni-Al系合金的有序无序转变,发现Ni3Al为一级相变,其晶格常数随长程有序度呈线性变化,而NiAl为二级相变,品格常数则呈非线性变化,此不同的转变规律是与相变类型有关,而不是完全由有序无序转变中原子构型力学平衡条件所决定.一级相变晶格常数变化是线性的,二级相变为非线性的.The lattice parameter variation of stoichiometric Ni3Al and NiAl during the order-disorder transformation was studied based on the embedded atom method (EAM). The order-disorder transformation for Ni3Al is of the first order transition, and the lattice parameter changes linearly along with the long range order parameter. NiAl is in the second order transition, and the relationship between the lattice parameter and the long range order parameter is nonlinear. The lattice parameter variation during the order-disorder transformation depends on both the phase transition type and the mechanical equilibrium condition. The lattice parameter should change linearly for the first order transition and nonlinearly for the second order transition.

关 键 词：Ni-Al系合金 有序无序转变 晶格常数 原子构型 相变 EAM势 金属间化合物 

分 类 号：TG146.15[一般工业技术—材料科学与工程] TG111.5[金属学及工艺—金属材料]