【作者】 陈律； 彭平； 李贵发； 胡艳军； 周惦武； 张为民；

【Author】 Chen Lv Peng Ping Li Guifa Hu YanjunZhou Dianwu Zhang Weimin( Changsha Aeronautical Vocational and Technical College, Changsha,410124) ( School of Materials Science & Engineering, Hunan University, Changsha, 410082)

【机构】 湖南大学材料科学与工程学院； 长沙航空职业技术学院；

【摘要】 本文采用第一原理赝势平面波方法研究了L1₀型TiAl金属间化合物中掺入Mn、Nb后电子结构和价键结构。通过合金原子形成热得出:Mn优先占据Al点阵位置,Nb优先占据Ti点阵位置。Mulliken聚居数分析发现:Mn和Nb合金化后,分别降低了（001）和（002）面内的原子间键合强度,掺入Nb还降低了层间的原子间键合强度;而掺入Mn,则使层间原子间键合强度增加。整体上来讲,掺入Mn有利于改善TiAl的室温脆性,而掺入Nb,不利于改善TiAl的室温脆性。更多还原

【Abstract】 First-Principles pseudopotential plane-wave method is applied to study the electronic structureand bonding characteristics of L1₀-TiAl intermetallic compound alloyed with Mn or Nb. By analyzingthe forming enthalpy, it is found that Mn prefer to occupy the Al sites, while Nb is favored to occupyTi sites. Mulliken population analysis showed that the bonding strength of （001） and （002） intralayersin L1₀-TiAl supercell decrease when TiAl is alloyed by Mn or Nb. And Nb addition also reduced the bonding strength of the interlayer, while Mn addition make the bonding strength of the interiayer increase. After compared the ratio of intra-layer bonding strength and interlayer bonding strength, it is found Mn addition is more helpful than Nb addition to improve the room temperature brittleness of L1₀-TiAl intermetallic compound.更多还原