Using the first-principles plane-wave pseudo-potential method based on density functional theory,the effect of vacancy and anti-position defect on the mechanical and thermal properties of B2-NiSc intermetallics were d...Using the first-principles plane-wave pseudo-potential method based on density functional theory,the effect of vacancy and anti-position defect on the mechanical and thermal properties of B2-NiSc intermetallics were discussed in detail.Several parameters,such as the shear modulus,bulk modulus,modulus of elasticity,C11-C12,the Debye temperature and Poisson's ratio,have been calculated to evaluate the effect of vacancy and anti-position defect on the hardness,ductility and thermal properties of B2-NiSc intermetallics.The results show that VNi,ScNi,VSc and NiSc the four point defects all make the crystal hardness decrease and improve plasticity of B2-NiSc intermetallics.The entropy,enthalpy and free energy of VNi,ScNi,VSc and NiSc are monotonously changed as temperature changes.From the perspective of free energy,NiSc is the most stable,while ScNiis the most unstable.Debye temperature of NiSc intermetallics with four different point defects shows VNi,ScNi,VSc and NiScthe four point defects all reduce the stability of B2-NiSc intermetallics.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.51301063,51571086)the Talent Introduction Foundation of Henan Polytechnic University(No.Y-2009)
文摘Using the first-principles plane-wave pseudo-potential method based on density functional theory,the effect of vacancy and anti-position defect on the mechanical and thermal properties of B2-NiSc intermetallics were discussed in detail.Several parameters,such as the shear modulus,bulk modulus,modulus of elasticity,C11-C12,the Debye temperature and Poisson's ratio,have been calculated to evaluate the effect of vacancy and anti-position defect on the hardness,ductility and thermal properties of B2-NiSc intermetallics.The results show that VNi,ScNi,VSc and NiSc the four point defects all make the crystal hardness decrease and improve plasticity of B2-NiSc intermetallics.The entropy,enthalpy and free energy of VNi,ScNi,VSc and NiSc are monotonously changed as temperature changes.From the perspective of free energy,NiSc is the most stable,while ScNiis the most unstable.Debye temperature of NiSc intermetallics with four different point defects shows VNi,ScNi,VSc and NiScthe four point defects all reduce the stability of B2-NiSc intermetallics.