Rank-1 Connection of Kink Bands Formed by Non-Parallel Shears

Abstract

The geometry of kink bands with the general shear direction on the unique slip plane was formulated and the connection between two kink bands formed by non-parallel shears on the slip plane was examined using rank-1 connection. For a kink deformation in a metal with a hexagonal lattice, we derived an equation that decomposes the general shear direction into two ©aª basal slips. The rotation axis of the misorientation of kink band moves away rapidly from h0 " 110i to h1 " 210i as the second ©aª basal shear component increased. We proved that any two kink bands formed by non-parallel basal shears can be rank-1 connected to each other. In addition to the wedge disclination, a mixed disclination at the junction of two kink bands formed by non-parallel basal shears was found.

Numerical Analysis of Disclinations in Connecting Kink Bands Formed by Multiple Basal Shear

“…1 " 120, a 4 = [0001]//e z . 38) The shear direction s on the basal plane is assumed to form an angle ¡ with e y . The magnitude of the shear is expressed as «s« = s. The body treated in this analysis is elastoplastic body.…”

“…Twist-type disclination appears in the trivial connection but is not considered in this study. 38) 3.1.3 s and ¡ dependence of the normal vector and Frank vector The ¡ dependence of ! and m is shown in this section.…”

“…Therefore, we extended the kink model to three dimensions by assuming the case where multiple basal slips are active and considering the slip in any direction on the basal plane as a composite of multiple basal slips. 38) The analysis shows that wedge disclination or mixed disclination, which is a mixture of wedge and twist disclinations, occurs when kink bands connect with each other, even in the case of three-dimensional deformation. However, the previous report only showed the existence of the disclination without clarification of the type and the power of the disclination.…”

Clustering Analysis of Acoustic Emission Signals during Compression Tests in Mille-Feuille Structure Materials

“…11,12,1517) Hagihara et al investigated the role of the deformation kink on the mechanical properties of Mg alloys with LPSO structure and clarified that kink-band strengthening is one of the predominant mechanisms for high yield stress of those alloys. 13) Inamura et al 18) explained the geometry of kink bands with the general shear direction on the unique slip plane based on rank-1 connection. It is worth noting that kink deformation was also found in other metals such as Cd 19) and Zn.…”

Semi-discrete modeling of systems of wedge disclinations and edge dislocations via the Airy stress function method

“…In crystal plasticity, disclinations (with their various configurations, such as isolated wedge disclinations, disclination dipoles, and even quadrupoles) have been recognized to play an important role in the kinematic accommodation of special morphologies of plastic kink bands caused by rotational stretches of the lattice [71,64,67,96]. Modeling and analysis of kinking has recently captured the interest of metallurgists in relation to a novel strengthening mechanism observed in certain classes of Mg-based alloys exhibiting Long-Period Stacking Order (LPSO) phase [68,1].…”