Highlights

• Effect of powerless boundaries along with the effect of the relative orientation of the boundary to the grains.

• A decomposition of dislocation densities at the boundary.

• Distinct observation of dislocation transmission through the boundary.

• A misconception in the literature which renders micro-free GB as a GNDs-free interface is addressed.

• A micro-hard boundary layer enforces the dislocations to flux only in the tangential direction as observed in experiments.