A one-dimensional(1 D) self-organized array composed of dislocation and anti-dislocation is analytically investigated in the frame of Peierls theory. From the exact solution of the Peierls equation, it is found that t...A one-dimensional(1 D) self-organized array composed of dislocation and anti-dislocation is analytically investigated in the frame of Peierls theory. From the exact solution of the Peierls equation, it is found that there exists strong neutralizing effect that makes the Burgers vector of each individual dislocation in the equilibrium array smaller than that of an isolated dislocation. This neutralizing effect is not negligible even though dislocations are well separated. For example, when the distance between the dislocation and the anti-dislocation is as large as ten times of the dislocation width, the actual Burgers vector is only about 80% of an isolated dislocation. The neutralizing effect originates physically from the power-law asymptotic behavior that enables two dislocations interfere even though they are well separated.展开更多
The core structure,Peierls stress and core energy,etc.are comprehensively investigated for the 90°dislocation and the 60°dislocation in metal aluminum using the fully discrete Peierls model,and in particular...The core structure,Peierls stress and core energy,etc.are comprehensively investigated for the 90°dislocation and the 60°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°dislocation,the core clearly dissociates into two partial dislocations with the separating distance D~12?,and the Peierls stress is very smallσp<1 k Pa.The nearly vanishing Peierls stress results from the large characteristic width and a small step length of the 90°dislocation.The 60°dislocation dissociates into 30°and 90°partial dislocations with the separating distance D~11A.The Peierls stress of the 60°dislocation grows up from1 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°dislocation and the 60°dislocation.The core structures theoretically predicted at T=0 K are also confirmed by the first principle simulations.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11874093)
文摘A one-dimensional(1 D) self-organized array composed of dislocation and anti-dislocation is analytically investigated in the frame of Peierls theory. From the exact solution of the Peierls equation, it is found that there exists strong neutralizing effect that makes the Burgers vector of each individual dislocation in the equilibrium array smaller than that of an isolated dislocation. This neutralizing effect is not negligible even though dislocations are well separated. For example, when the distance between the dislocation and the anti-dislocation is as large as ten times of the dislocation width, the actual Burgers vector is only about 80% of an isolated dislocation. The neutralizing effect originates physically from the power-law asymptotic behavior that enables two dislocations interfere even though they are well separated.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11874093 and 11974062)。
文摘The core structure,Peierls stress and core energy,etc.are comprehensively investigated for the 90°dislocation and the 60°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°dislocation,the core clearly dissociates into two partial dislocations with the separating distance D~12?,and the Peierls stress is very smallσp<1 k Pa.The nearly vanishing Peierls stress results from the large characteristic width and a small step length of the 90°dislocation.The 60°dislocation dissociates into 30°and 90°partial dislocations with the separating distance D~11A.The Peierls stress of the 60°dislocation grows up from1 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°dislocation and the 60°dislocation.The core structures theoretically predicted at T=0 K are also confirmed by the first principle simulations.
