Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (1): 10204-010204.doi: 10.1088/1674-1056/22/1/010204

• GENERAL • 上一篇    下一篇

Effect of grain boundary sliding on the toughness of ultrafine grain structure steel: a molecular dynamics simulation study

谢红献a, 刘波a, 殷福星b, 于涛c   

  1. a School of Mechanical Engineering, Hebei University of Technology, Tianjin 300132, China;
    b Materials Research Institute for Energy Equipments, China First Heavy Industries, China;
    c Central Iron and Steel Research Institute, Beijing 100081, China
  • 收稿日期:2012-06-10 修回日期:2012-06-26 出版日期:2012-12-01 发布日期:2012-12-01

Effect of grain boundary sliding on the toughness of ultrafine grain structure steel: a molecular dynamics simulation study

Xie Hong-Xian (谢红献)a, Liu Bo (刘波)a, Yin Fu-Xing (殷福星)b, Yu Tao (于涛)c   

  1. a School of Mechanical Engineering, Hebei University of Technology, Tianjin 300132, China;
    b Materials Research Institute for Energy Equipments, China First Heavy Industries, China;
    c Central Iron and Steel Research Institute, Beijing 100081, China
  • Received:2012-06-10 Revised:2012-06-26 Online:2012-12-01 Published:2012-12-01
  • Contact: Xie Hong-Xian E-mail:hongxianxie@163.com

摘要: Molecular dynamics simulations are carried out to investigate the mechanisms of low-temperature impact toughness of the ultrafine grain structure steel. The simulation results suggest that the sliding of the {001}/{110} type and {110}/{111} type grain boundary can improve the impact toughness. Then, the mechanism of grain boundary sliding is studied and it is found that the motion of dislocations along the grain boundary is the underlying cause of the grain boundary sliding. Finally, the sliding of the grain boundary is analysed from the standpoint of the energy. We conclude that the measures which can increase the quantity of the {001}/{110} type and {110}/{111} type grain boundary and elongate the free gliding distance of dislocations along these grain boundaries will improve the low-temperature impact toughness of the ultrafine grain structure steel.

关键词: molecular dynamics simulations, grain boundary, crack, ultrafine grain structure steel

Abstract: Molecular dynamics simulations are carried out to investigate the mechanisms of low-temperature impact toughness of the ultrafine grain structure steel. The simulation results suggest that the sliding of the {001}/{110} type and {110}/{111} type grain boundary can improve the impact toughness. Then, the mechanism of grain boundary sliding is studied and it is found that the motion of dislocations along the grain boundary is the underlying cause of the grain boundary sliding. Finally, the sliding of the grain boundary is analysed from the standpoint of the energy. We conclude that the measures which can increase the quantity of the {001}/{110} type and {110}/{111} type grain boundary and elongate the free gliding distance of dislocations along these grain boundaries will improve the low-temperature impact toughness of the ultrafine grain structure steel.

Key words: molecular dynamics simulations, grain boundary, crack, ultrafine grain structure steel

中图分类号:  (Molecular dynamics and particle methods)

  • 02.70.Ns
83.60.Uv (Wave propagation, fracture, and crack healing) 61.72.Ff (Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.))