Dynamic interaction between dislocation and diffusing solutesZ. J. Chen1, 2, Q. C. Zhang2 and X. P. Wu2
1 College of Materials Science and Engineering, Hefei University of Technology Hefei 230009, PRC
2 CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China - Hefei 230027, PRC
received 6 December 2004; accepted in final form 23 May 2005
published online 22 June 2005
The dynamic dislocation-solute interaction is studied through a system integration method where a feedback mechanism is introduced to characterize the competition of pinning and depinning effects. The results self-consistently exhibit three branches of the interaction, two stable branches at low and high strain rate (or dislocation velocity) which correspond to the effective pinning or unpinning of dislocation, respectively, and a metastable one at the intermediate strain rate where negative strain rate sensitivities result from dynamic strain ageing. This unified description should be helpful to the studies of rate-softening plastic instability.
61.72.Yx - Interaction between different crystal defects; gettering effect.
83.60.Fg - Shear rate dependent viscosity.
© EDP Sciences 2005