Acta Mechanica Solida Sinica

, Volume 20, Issue 2, pp 103–109 | Cite as

Effects of dislocation configuration, crack blunting and free surfaces on the triggering load of dislocation sources

  • Zhixing Lu
  • Xuyue Wang
  • Shouwen Yu
  • Xiqiao Feng


The effects of dislocation configuration, crack blunting and free surfaces on the triggering load of dislocation sources in the vicinity of a crack or a wedge tip subjected to a tensile load in the far field are investigated. An appropriate triggering criterion for dislocation sources is proposed by considering the configurational forces acting on each dislocation. The triggering behaviors of dislocation sources near the tips of a crack and a wedge are compared. It is also found that the blunting of crack tip and the presence of free surfaces near the crack or the wedge have considerable influences on the triggering load of dislocation sources. This study might be of significance to gaining a deeper understanding of the brittle-to-ductile transition of materials.

Key words

dislocation source crack wedge brittle-to-ductile transition 


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Copyright information

© The Chinese Society of Theoretical and Applied Mechanics and Technology 2007

Authors and Affiliations

  • Zhixing Lu
    • 1
  • Xuyue Wang
    • 2
  • Shouwen Yu
    • 1
  • Xiqiao Feng
    • 1
  1. 1.Department of Engineering MechanicsTsinghua UniversityBeijingChina
  2. 2.Department of Basic Science, Graduate School at ShenzhenHarbin Institute of TechnologyShenzhenChina

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