Effect of Co Content and Temperature on Shear Mechanical Properties of Nano‐Polycrystalline Ni–Co Alloy

Abstract

Herein, the effects of different Co content and temperature factors on the shear mechanical properties of nano‐polycrystalline nickel–cobalt alloy are analyzed by molecular dynamics (MD) simulations. It is found in the work that the highest shear modulus of 63.03 GPa is obtained when the Co content is 10%, attributed to the lattice distortion caused by the difference in the lattice parameters between two elements. During the shearing process, the multilevel twins are present with intensification of the deformation process, resulting in excellent dynamic shear performance. Shockley dislocations will drive the stacking faults and other partial dislocations to constitute a tetrahedral edge, and finally forms a tetrahedral structure. In addition, as the temperature of the shear environment increases, the highest strain and stress decrease. The grain boundary atoms increase significantly, and the atoms inside the grains decrease accordingly. As the degree of atomic disorder increases, the grain boundaries will melt gradually. The decrease of partial dislocation density can weaken the entanglement effect caused by dislocations. The previous conclusions promote the product development and application of nano‐polycrystalline alloys in the future, and provide important guidance significant for the engineering application of nickel–cobalt alloys.

Effect of Bi content and temperature on the shear mechanical properties of Fe-Bi nanocomposites: a molecular dynamics study

“…Hua et al [29] employed MD methods to study the shear mechanical properties of graphene/ copper composites and discovered that the incorporation of graphene significantly enhances the shear strength of the composite material. Chen et al [30] conducted MD simulations on the effects of varying Co content and temperature on the shear mechanical properties of Ni-Co alloys and found that the incorporation of Co atoms into pure Ni causes lattice distortion, increasing the resistance to dislocation motion and thereby enhancing the material's strength. Chang et al [31] utilized MD simulations to investigate the impact of grain size, temperature, and gradient Al content on the deformation mechanism of Ni 50-x Ti 50 Al x polycrystalline alloys, identifying the content of Al atoms and temperature as primary factors affecting the material's failure mechanism.…”