Explicit incorporation of cross-slip in a dislocation density-based crystal plasticity model

Abstract

We present a crystal plasticity model that incorporates cross-slip of screw dislocations explicitly based on dislocation densities. The residence plane of screw dislocations is determined based on a probability function defined by activation energy and activation volume of cross-slip. This enables the redistribution of screw-dislocations and dislocation density patterning due to the effect of stacking fault energy. The formulation is employed for explaining the cross-slip phenomenon in aluminium during uniaxial tensile deformation of ⟨100⟩ single crystal and a single slip orientation of single crystal, and compare the results with experimental observations. The effect of cross-slip on the stress–strain evolution is seen using this explicit treatment of cross-slip.

Keywords:

• crystal plasticity
• dislocations
• cross-slip
• fcc crystal
• dislocation density patterning

Acknowledgements

We are grateful to Professor John P. Hirth for fruitful discussions, comments and suggestions on the manuscript. HMZ would like to gratefully acknowledge the support from NSF to WSU under Grant number CMMI-6103043.