纳米多晶铝的弹性和热力学性质研究  

Elastic and Thermodynamic Properties of the Nanocrystalline Al

作　　者：朱艳花 薄锐[1] 崔新林[1] 

机构地区：[1]山西大学理论物理研究所,山西太原030006

出　　处：《山西大学学报（自然科学版）》2016年第1期68-73,共6页Journal of Shanxi University(Natural Science Edition)

基　　金：国家自然科学基金(11302121)

摘　　要：利用Voronoi几何法搭建了纳米多晶金属铝,对初始结构进行弛豫和退火来降低由大角度晶界带来的高应力和高能量。在弛豫和退火过程中监测了体系结构、平均内应力、平均能量等在各个过程的变化情况,最终获得了稳定的结构。随后利用经典分子动力学模拟方法计算了不同晶粒大小纳米金属铝的弹性常数和一些热力学参数。计算结果表明,金属铝的弹性常数随着晶粒的增大有所变化,C11、C44随着晶粒的增大而增大,C12则是减小的,模拟结果与其他计算数据和实验数据进行了对比;随后计算了不同晶粒大小体系的杨氏模量、体弹模量、剪切模量等热力学参量,并与实验数据对比分析。The initial nanocrystalline aluminum samples were assembled by Voronoi geometrical method, then these samples were relaxed to reduce the high energy and stress,which was caused by the unphysical grain boundaries. The structures, the average internal stresses, as well as energies were observed during the relaxtion processes. The influence of grain size on the elastic constants and thermodynamic properties of the computer generated samples were analyzed. With the increase of grain size,the vaule of C11 and C44 get big ger,while C12get more smaller. The results shows that the bulk modulus,shear modulus,young＇s modulus at final state are close to the experimental datas.

关 键 词：纳米多晶铝 弛豫 弹性常数 热力学参数 

分 类 号：O469[理学—凝聚态物理]