A dislocation-based model for creep recovery in ice
A dislocation-based model for creep recovery in ice
复制标题
基于位错的冰蠕变恢复模型
DOI：
10.1080/14786430412331284496
复制
发表时间：
2004
影响因子：
1.6
通讯作者：
D. Cole
中科院分区：
文献类型：
--
作者：
D. Cole
蠕变恢复应变在多晶冰中表现显著，其应力依赖性与冰的类型和变形历史密切相关。虽然人们普遍认为蠕变恢复应变在很大程度上归因于位错，但一个基于位错的模型来校正两种重要冰类型（淡水冰和海冰）的观察差异，以前没有出现过；这种模式的发展形成了当前努力的目标。该模型考虑了基本的位错分布，采用了先前工作中的位错密度-应力关系，并使用了滑移线间距随应力增加而减小的经验表达式。位错过程被认为是在亚晶粒大小的区域上进行的，并且考虑了与邻近区域的相对运动相关的应变。当外加应力足够高时，该模型考虑了位错倍增和滑移线间距的减小。该模型解释了观测到的d…
Creep recovery strain is significant in polycrystalline ice, and its stress dependence is strongly dependent on ice type and deformation history. Although it is generally recognized that creep recovery strain is largely attributable to dislocations, a dislocation-based model that rectifies the observed differences in two important ice types (freshwater and sea ice) has not previously emerged; and the development of such a model forms the goal of the present effort. The model considers basal dislocation distributions, employs a dislocation density–stress relationship from previous work, and uses an empirical expression for the decrease in slip-line spacing with increasing stress. The dislocation processes are taken to operate over a subgrain-sized domain, and the strain associated with the relative motion of neighbouring domains is considered. The model accounts for dislocation multiplication and the decrease in slip-line spacing if the applied stress is sufficiently high. The model explains the observed d...