嵌入原子法研究Ni_3Al中点缺陷以及Re择优占位和集团化  

Study of the point defect, Re site, and Re cluster in Reembedded Ni_3Al using the embedded atom method

作　　者：于松[1] 王崇愚[1] 于涛[1] 

机构地区：[1]钢铁研究总院,北京100081

出　　处：《物理学报》2007年第6期3212-3218,共7页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(973)项目(批准号:2006CB605102);国家自然科学基金(批准号:90306016)资助的课题~~

摘　　要：基于纯金属元素Ni,Al和Re的基本物理性质,建立了一个Ni-Al-Re三元体系的分析型嵌入原子多体势.结合分子动力学计算了Ni3Al的平衡晶格常数、弹性模量、结合能、空位形成能以及反位置缺陷形成能,并分析了Ni3Al中点缺陷的存在形式.计算结果表明,当成分偏离理想化学配比时出现反位置缺陷.同时研究了Re在Ni3Al中的择优占位以及Re在Ni3Al和Ni中的集团化行为.计算结果表明,Re在Ni3Al中优先置换Al的位置,且发现当Re原子团的尺寸接近于11时,Re原子团的长大趋势变弱.计算结果与实验以及其他的理论计算结果相符合.An analytical embedded atom method model of Ni-Al-Re system is constructed on the basis of the physical properties of pure constituents Ni, Al, and Re. The characteristic properties of Ni3Al, including equilibrium lattice constant, elastic constants, cohesive energy, vacancy formation energy, and antisite defect formation energy, are calculated. The types of point defects in Ni3Al are discussed, and it is shown that the point defect is the antisite defect in the nonstoichiometric case. Furthermore, the occupation site of Re in Ni3 Al is analyzed, the clustering of Re in Ni3 Al and Ni are also studied. The calculation results show that the occupational site of Re is the Al site, and that the growth tendency of Re cluster becomes weak when the size of Re cluster reaches to 11 A. The present calculations are in agreement with the experiment and the theoretical results obtained by other authors.

关 键 词：嵌入原子势 NI3AL RE 占位 集团化 

分 类 号：O771[理学—晶体学]