论文部分内容阅读
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,C_(11)-C_(12),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 V_(Ni),Sc_(Ni),V_(Sc)and Ni_(Sc)the four point defects all make the crystal hardness decrease and improve plasticity of B2-NiSc intermetallics.The entropy,enthalpy and free energy of V_(Ni),Sc_(Ni),V_(Sc)and Ni_(Sc)are monotonously changed as temperature changes.From the perspective of free energy,Ni_(Sc)is the most stable,while Sc_(Ni)is the most unstable.Debye temperature of NiSc intermetallics with four different point defects shows V_(Ni),Sc_(Ni),V_(Sc)and Ni_(Sc)the four point defects all reduce the stability of B2-NiSc intermetallics.
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. Scope parameters, such as the shear modulus, bulk modulus, modulus of elasticity, C_ (11) -C_ (12), 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 V_ (Ni), Sc_ (Ni), V_ (Sc) and Ni_ (Sc) the four point defects all make the crystal hardness decrease and improve plasticity of B2-NiSc intermetallics.The entropy, enthalpy and Sc_ (Ni), V_ (Sc) and Ni_ (Sc) are monotonously changed as temperature changes. From the perspective of free energy, Ni_ (Sc) is the most stable, while Sc_ (Ni) ) is the most unstable. Debye temperature of NiSc intermetallics with four different point defects V_ (Ni), Sc_ ( Ni), V_ (Sc) and Ni_ (Sc) the four point defects all reduce the stability of B2-NiSc intermetallics.