Dislocation models of interfacial shearing induced by an approaching lattice glide dislocation
Dislocation models of interfacial shearing induced by an approaching lattice glide dislocation
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DOI：
10.1016/j.ijplas.2012.08.005
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发表时间：
2013-02
影响因子：
9.8
通讯作者：
H. Chu;Jian Wang;I. Beyerlein;E. Pan
中科院分区：
文献类型：
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作者：
H. Chu;Jian Wang;I. Beyerlein;E. Pan
当晶格滑移位错以相对低的剪切强度接近双金属界面时，它导致界面剪切。界面剪切由界面位错的形核和生长来调节，界面位错与进入的位错具有吸引力的相互作用。因此，存在一个临界长度尺度，在该尺度下，对进入的晶格滑移位错的净力可以从最初的排斥力转变为吸引力。在本文中，我们开发了基于位错的界面剪切模型，以代表这种机制的界面/位错的相互作用在连续尺度。三个版本的设计具有不同程度的复杂性，因此计算成本：连续剪切模型（CSM），双稳态CSM模型（SCSM），和单位错剪切模型（SDSM）。我们用各向异性双材料的绿色函数方法模拟了这三种模型的相互作用过程。所有这三个模型发现，临界长度尺度的位错成为吸引到界面增加的界面剪切阻力降低。虽然最复杂的模型的三个，CSM，表现最好的，SCSM和SDSM更有利于实施到更高的长度尺度的位错动力学模型。
When a lattice glide dislocation approaches a bi-metal interface with relatively low shear strength, it causes the interface to shear. Interfacial shearing is accommodated by the nucleation and growth of interfacial dislocations, which have an attractive interaction with the incoming dislocation. Thus a critical length scale exists at which the net force on the incoming lattice glide dislocation can transition from being initially repulsive to attractive. In this paper, we develop dislocation-based interface shear models in order to represent this mechanism of interface/dislocation interaction at the continuum scale. Three versions are devised with different degrees of complexity and hence computational cost: the continuous shear model (CSM), simplified-CSM model (SCSM), and single dislocation shear model (SDSM). We simulate the interaction processes with these three models by means of a Green’s function method for an anisotropic bimaterial. All three models find that the critical length scale at which the dislocation becomes attracted to the interface increases as the interfacial shear resistance decreases. While the most complex model of the three, the CSM, performs the best, the SCSM and SDSM are more advantageous for implementation into higher-length scale dislocation dynamics models.