Molecular dynamics study of the effect of lithium on the tensile mechanical behavior of alpha-iron

doi:10.7523/j.ucas.2020.0024

Abstract

Abstract: Liquid lithium first wall is an advanced concept in the field of magnetic confinement fusion. Compared with the traditional solid wall materials, more and more experiments have shown that liquid lithium wall has unique advantages, which can not only effectively solve a series of problems faced by solid wall materials such as sputtering and tritium retention, but also significantly improve the constraint performance of core plasma. However, liquid lithium has brought severe corrosion problems to most metal materials, and the microstructure changes caused by corrosion will inevitably lead to the degradation of the macroscopic mechanical properties of materials. For structural materials, the degradation of mechanical properties will bring safety risks to the entire device. Based on this, the uniaxial tensile simulations of single crystal alpha-iron were carried out by using molecular dynamics, and the effects of lithium atoms on the plastic deformation behavior and yield stress were analyzed in this paper. The results show that lithium atoms can significantly suppress the phase transition, change the plastic deformation mode of alpha-iron, and affect the yield stress and its relationship with temperature.

Key words: molecular dynamics, uniaxial tension, mechanical properties, iron, lithium

CLC Number:

O482.1

WEI Wei, YU Xin'gang. Molecular dynamics study of the effect of lithium on the tensile mechanical behavior of alpha-iron[J]. Journal of University of Chinese Academy of Sciences, 2022, 39(1): 13-20.

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