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Title: Atomistic Simulation of Interstitial Dislocation Loop Evolution under Applied Stresses in BCC Iron

Journal Article · · Physica Status Solidi. A, Applications and Materials Science
 [1];  [2];  [3];  [1];  [2];  [3];  [2];  [1]
  1. School of Physics, State Key Laboratory of Crystal Materials Shandong University Shandong Jinan 250100 P.R. China
  2. Institute of Modern Physics Chinese Academy of Sciences LanZhou 73000 P.R. China
  3. Pacific Northwest National Laboratory P. O. Box 999 Richland WA 99352 USA

Evolution of an interstitial 1/2 dislocation loop under tensile, shear, and torsion stresses is studied with molecular statics method. Under a tensile stress, the dependence of ultimate tensile strength on size of loop is calculated. The formation of small shear loops around the initial prismatic loop is confirmed as an intermediate state to form the final dislocation network. Under a shear stress, the rotation of a loop is observed not only by a change of the habit plane but also through a transformation between a shear and a prismatic loop. Under torsion, a perfect BCC crystal may undergo a BCC to FCC or BCC to HCP transformation. The present work indicates that a 1/2 loop can delay these transformations, resulting in the formation of micro‐crack on the surface.

Sponsoring Organization:
USDOE
Grant/Contract Number:
NONE; AC05-76RL01830
OSTI ID:
1408055
Alternate ID(s):
OSTI ID: 1439672
Journal Information:
Physica Status Solidi. A, Applications and Materials Science, Journal Name: Physica Status Solidi. A, Applications and Materials Science Journal Issue: 1 Vol. 215; ISSN 1862-6300
Publisher:
Wiley Blackwell (John Wiley & Sons)Copyright Statement
Country of Publication:
Germany
Language:
English

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