Department of Mathematics and Physics, Hebei Petroleum University of Technology, Chengde, China.
PLoS One. 2023 Jul 7;18(7):e0288331. doi: 10.1371/journal.pone.0288331. eCollection 2023.
The fundamental properties of dislocations in diamond-structured Si and sphalerite-structured GaAs, InP and CdTe are investigated based on lattice theory of dislocation, hoping to provide some theoretical references in improving the properties of related materials. The influences of the surface effect(SE) and elastic strain energy on the structure and mechanical property of dislocation are discussed systematically. After considering the SE, the core width of dislocation becomes wider due to the elastic interaction between atoms becomes stronger. Compared to glide partial dislocation, the correction of SE to shuffle dislocation is more obvious. Both the SE and the elastic strain energy affect the energy barrier and Peierls stress of dislocation. The influence of SE on energy barrier and Peierls stress mainly results from the misfit energy and elastic strain energy become lower when the core of dislocation becomes wider. While the influence of elastic strain energy on energy barrier and Peierls stress mainly results from the cancellation between misfit energy and elastic strain energy for they possess comparable amplitudes but opposite phases. In addition, it is deduced that for the studied crystals, the shuffle dislocations control the deformation at medium and low temperatures, while glide partial dislocations are responsible for high temperature plasticity.
基于位错的晶格理论，研究了金刚石结构的 Si 和闪锌矿结构的 GaAs、InP 和 CdTe 中位错的基本性质，希望为提高相关材料的性能提供一些理论参考。系统讨论了表面效应（SE）和弹性应变能对位错结构和力学性能的影响。考虑 SE 后，由于原子间的弹性相互作用增强，位错的核宽度变宽。与滑移部分位错相比，SE 对位错的校正更为明显。SE 和弹性应变能都影响位错的能垒和派尔斯应力。SE 对位错能垒和派尔斯应力的影响主要来自于当位错核变宽时，失配能和弹性应变能降低。而弹性应变能对位错能垒和派尔斯应力的影响主要来自于失配能和弹性应变能的抵消，因为它们具有相当的幅度但相位相反。此外，推断对于研究的晶体，在中低温下， shuffle 位错控制变形，而滑移部分位错负责高温塑性。
