【摘要】 采用第一原理赝势平面波方法计算了NiAl超胞合金化的几何与力学性质结构,应用几个力学参数表征和评判了合金化元素对NiAl金属间化合物延/脆性及其硬度的影响.结果发现:Cr,Mn,Fe,Co和Cu合金化均可提高NiAl金属间化合物的硬度,其增加次序为:Mn>Co>Fe>Cr>Cu,但合金化元素含量过高(6.25at%),却使NiAl金属间化合物的延展性降低,其降低次序与硬度增加的次序相反.更多还原

【Abstract】 The geometrical and electronic structures of NiAl supercells were calculated by the first-principle pseudopotential plane wave methods based on the density fuctional theory.Several mechanical parameters were used to characterize and assess the alloying effect of the element on the brittle or ductile behavior as well as the hardness of NiAl intermetallic compounds.The result showed that addition of Cr or Mn,Fe,Co,Cu could enhance the hardness of compounds in the following order: Cu,Cr,Fe,Co,Mn,but the ductity of compounds decreased with an opposite order to the increase of their hardness because of their high contents of addition(eg.6.25at%).更多还原