Grain Boundary Accumulation of Geometrically Necessary Dislocation and Asymmetric Deformation in Compatible-type Bicrystals with Tilt Angle Grain Boundary under Tensile Loading

Multi-Body Interaction of Crystal Grains in Compatible-Type Tricrystals under Tensile Loading and Formation of Disclination-Type Displacement Field

“…Since the value of the Schmid factor of the primary slip system (11 1)[101] is about 0.5; and under minute deformation, the deformation of the model advances due to the single slip in the primary slip system (refer to table 2), the plastic strain components The initial crystal orientation of crystal grains 1, 2 and 3 is selected as a combination of the same angle α formed by the slip direction ( ) 9th b and the direction of load difference from 45° to the high-and low-angle sides (6) , (1) α = (2) α =46°， (3) α =44°. Here, the superscripts indicate the crystal grain numbers.…”

“…For relate and evaluate the non-uniform deformation and the GN dislocation structure formation, as well as the case of symmetric type bicrystals (6) (19) , the slip deformation in the tricrystals is understood to have two stages, as shown in Figs Mutual interaction between crystal grains and non-uniform deformation occur to satisfy boundary conditions and the continuity of the displacement through the grain boundary. The displacement field around the grain boundary triple junction is similar to that for wedge disclination deformation, as shown in Figs.…”

“…Multi-body interaction between the crystal grain works by the shape change due to the slip deformation in the active slip systems, when the crystal grain is three or more as well as the case of the bicrystals (6)(7)(8) . Therefore, it is understood that GN dislocation structure that causes a non-uniform deformation in the crystal grain and corresponds to kink band is formed (6) .…”

“…We have performed crystal plasticity analysis of tensile deformation in compatible-type bicrystals satisfy the requirement in which the effects of the elastic incompatibility stress and the plastic stain incompatibility does not work (1) (5) , and stated in a previous study that non-uniform deformation with GN dislocation structure correspond to the kink bands and secondary slip bands (6) were formed in the crystal grains depended on the boundary condition of external loading (7) and the initial crystal orientation (8) , even if the grain boundary effect, in which had been thought to be the main cause of the non-uniform deformation, was removed from analysis model. It was described to cause these phenomena by mutually constrained the shape change of the crystal grain due to the slip deformation in the active slip systems by the boundary condition of external load and the grain boundary (6)(7)(8) .…”

“…It was described to cause these phenomena by mutually constrained the shape change of the crystal grain due to the slip deformation in the active slip systems by the boundary condition of external load and the grain boundary (6)(7)(8) .…”