Adiabatic Shear Bands in Simple and Dipolar Viscopolastic Materials

绝热剪切带是指在高速塑性变形过程中发生的局部化现象，如机械加工、冲击冲击载荷、弹道穿透和金属成形过程。由于剪切带被认为是材料断裂的前兆，因此了解这些现象以及抑制或增强其产生和发展的因素对耐用材料的生产至关重要。本研究将集中于：A)开发有效的算法来整合控制场方程，b)确定研究此类问题的最合适的本构模型，c)研究材料非均匀性建模的不同方法的影响，d)确定对剪切带的产生和后续发展有显著影响的材料参数。E)研究加载路径对剪切带萌生和生长的影响；f)研究两个或多个剪切带之间的相互作用；g)评估剪切带对材料造成的损伤。

Adiabatic shear banding is the name given to a localization phenomenon that occurs during high-rate plastic deformation, such as machining, shock impact loading, ballistic penetration, and metal forming processes. As shear bands are believed to be precursors to material fracture, a knowledge of these phenomena, and of factors that inhibit or enhance their initiation and growth, is essential to the production of durable materials. The study will concentrate on: a) developing efficient algorithms to integrate the governing field equations, b) identifying the most appropriate constitutive model for the study of such problems, c) studying the effect of different ways of modeling a material inhomogeneity, d) identifying material parameters that affect significantly the initiation and subsequent development of shear bands, e) studying the effect of the loading path on the initiation and growth of a shear band, f) investigating the interaction among two or more bands, and g) assessing the damage caused by a shear band to the material.