A general framework for dislocation models

Dislocations are important strain carriers of plasticity. We first revisit the recent progress in the forces and stresses used in dislocation modeling, particularly the Kanzaki and restoring stresses for dislocations. Then we discuss the relationship between these force/stress quantities, check their accuracy, and the locality assumption of the restoring stress used to describe the interactions between atoms across the slip planes. Generally, all analytic formulations cannot describe dislocation cores with an accuracy comparable to the true stress. Still, some stress quantities are more accurate than others, and it is possible to choose suitable quantities to improve existing models. We also revisit the dislocation models constructed based on these stress terms and find their common features. Our results show that the elastic stress is local instead of the restoring stress since the gamma surface used to calculate the former already includes interactions beyond the nearest neighbors. Finally, we discuss the opportunities for new dislocation models in a general framework.

Automated summary

This paper first reviews the recent progress in forces and stresses used in dislocation modeling, focusing on the Kanzaki and restoring stresses for dislocations. Then, the relationship between these force/stress quantities, their accuracy and the locality assumption of the restoring stress used to describe atom interactions across slip planes are discussed. The results show that some stress quantities are more accurate than others, and it is possible to choose suitable quantities to improve existing models. Common features of dislocation models constructed based on these stress terms are also analyzed. Additionally, opportunities for new dislocation models in a general framework are discussed.