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Dislocation-density kinematics: a simple evolution equation for dislocation density involving movement and tilting of dislocations

Published online by Cambridge University Press:  17 August 2017

A.H.W. Ngan
A.H.W. Ngan*
Affiliation:
Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
*
Address all correspondence to A.H.W. Ngan at hwngan@hku.hk
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Abstract

In this paper, a simple evolution equation for dislocation densities moving on a slip plane is proven. This equation gives the time evolution of dislocation density at a general field point on the slip plane, due to the approach of new dislocations and tilting of dislocations already at the field point. This equation is fully consistent with Acharya's evolution equation and Hochrainer et al.’s “continuous dislocation dynamics” (CDD) theory. However, it is shown that the variable of dislocation curvature in CDD is unnecessary if one considers one-dimensional flux divergence along the dislocation velocity direction.

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Type
Research Letters
Information
MRS Communications , Volume 7 , Issue 3 , September 2017 , pp. 583 - 590
Copyright
Copyright © Materials Research Society 2017 

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