Fe中<100>{010}刃位错芯结构的各向异性修正

在位错晶格理论基础上，采用改进的Peierls-Nabarro方程研究了Fe中<100>{010}刃位错在各向异性近似下的芯结构和Peierls应力. 各向异性近似下的晶格离散效应、切变模量和能量因子的表达式都已确切给出. 在这三个各向异性因素中，晶格离散效应和能量因子可以使位错宽度变窄，切变模量可以使位错宽度变宽. 相比于各向同性近似，各向异性近似下的位错宽度变窄了近20%，并且各向异性近似下的位错宽度与数值计算的结果相一致. 更为重要的是，各向异性使位错的Peierls应力数值几乎加倍，数量级也由 变成了 ，而这些都会显著影响位错的运动机制. 因此，各向异性对于位错来说非常重要，在研究位错芯结构以及运动机制时需要考虑各向异性的影响.

The anisotropic modification to the core structure and Peierls stress of the <100> {010} edge dislocation in Fe

Based on the dislocation lattice theory, the core structure and the Peierls stress of the <100>{010} edge dislocation in Fe have been determined by using the modified Peierls-Nabarro (P-N) equation in the elastically anisotropic approximation. The expressions of the lattice discrete effect and the shear modulus as well as the energy coefficient have been given explicitly. Among the three factors of anisotropy, and the lattice discrete effect and the energy coefficient can make the core width narrowed, the shear modulus can make the core width widened. Compared with the result in the isotropic approximation, the core width is nearly narrowed by 20 percent by the anisotropy, and the core width in the anisotropic approximation is still in agreement with the numerical simulations. Moreover, the Peierls stress of the dislocation is nearly doubled by the anisotropy, and the order of the magnitude of the Peierls stress is changed from MPa to GPa, and all these will affect the movement mechanism of the dislocation significantly. Therefore, the anisotropy is very crucial to the dislocation, and it should be considered in determining the core structure and the movement mechanism of the dislocation.