铬和镍的添加对Fe_3Al合金力学性能影响的DFT研究  

The DFT analyses of effect of chromium and nickel additions on the mechanical properties of Fe_3Al based alloys

作　　者：牛雪莲[1] 王立久[1] 孙丹[1] 

机构地区：[1]大连理工大学建设工程学部,建材研究所,大连116024

出　　处：《物理学报》2013年第3期310-315,共6页Acta Physica Sinica

基　　金："十一五"国家科技支撑计划重大项目(批准号:2006BAJ04A04);辽宁省教育厅(批准号:2008282)资助~~

摘　　要：利用第一原理研究了过渡金属元素Cr或Ni在Fe3Al合金中的优先占位行为及其合金化效应.计算结果表明:Cr或Ni的取代有助于Fe3Al合金体系更稳定,Cr优先占据FeI位,Ni优先占据FeII位.Fe2NiAl-II具有最小的剪切模量G,杨氏模量E和G/B值,因此Fe2NiAl-II合金的韧性、延展性最佳.态密度和电荷密度图表明,过渡金属元素的取代提高了它们与近邻基体原子之间的相互作用,削弱了Al和Fe的相互作用.Site preference behaviors of transition metal （TM） Cr and Ni in Fe3Al alloy and alloying effect are studied by using first-principles. Computational results show that the addition of TM is beneficial to the improvement of the stability of Fe3Al alloy;Cr atoms prefer to stay at FeI sites, while Ni atoms occupy FeII sites. Our investigations reveal that Fe2NiAl has lower bulk modulus B, shear modulus G and B/G than other （Fe3？yXy）Al （X=Cr, Ni;y=0,1,2） alloys, which turns out to be a brittle alloy. The analyses of density of states and electronic charge density indicate that additional TM improves the interaction between TM and neighboring host atoms of Fe3Al but weakens the interaction between Al and Fe.

关 键 词：合金化效应 第一原理 弹性性质 电子结构 

分 类 号：TG141[一般工业技术—材料科学与工程]