Core structure and Peierls stress of the 90° dislocation and the 60° dislocation in aluminum investigated by the fully discrete Peierls model

The core structure, Peierls stress and core energy, etc. are comprehensively investigated for the 90 degrees dislocation and the 60 degrees dislocation in metal aluminum using the fully discrete Peierls model, and in particular thermal effects are included for temperature range 0 <= T <= 900 K. For the 90 degrees dislocation, the core clearly dissociates into two partial dislocations with the separating distance D similar to 12 angstrom, and the Peierls stress is very small sigma (p) < 1 kPa. The nearly vanishing Peierls stress results from the large characteristic width and a small step length of the 90 degrees dislocation. The 60 degrees dislocation dissociates into 30 degrees and 90 degrees partial dislocations with the separating distance D similar to 11 angstrom. The Peierls stress of the 60 degrees dislocation grows up from 1 MPa to 2 MPa as the temperature increases from 0 K to 900 K. Temperature influence on the core structures is weak for both the 90 degrees dislocation and the 60 degrees dislocation. The core structures theoretically predicted at T = 0 K are also confirmed by the first principle simulations.

Automated summary

This study comprehensively investigates the core structure and properties of 90 degrees and 60 degrees dislocations in metal aluminum, revealing their differences under thermal conditions and minimal temperature influence on the core structures.