Fig. 1: Reversible migration of a 13.5° \(\big[ {1\bar 10} \big]\) low angle grain boundary (LAGB) in shear loading cycles.
From: Metallic nanocrystals with low angle grain boundary for controllable plastic reversibility
a An as-fabricated gold (Au) bicrystal with an LAGB. b, c Downward migration of the LAGB under leftward shear loading. d, e Upward migration of the LAGB under rightward shear loading. The directions of shear loading and GB migration in each cycle are shown by the yellow and red arrows, respectively. f–h Reversible migration of this LAGB in subsequent shear loading cycles. For clear demonstration, the top and bottom positions of the LAGB in each cycle are delineated by the yellow and light blue dotted lines, respectively. i The LAGB after the left shear in the fifth cycle. j Atomistic structure of the 13.5° \(\left[ {1\bar 10} \right]\) LAGB, which consists of aligned dislocations with a Burgers vector of 1/2 \(\left[ {01\overline{1}} \right]\). k GB migration distance versus shear diplacement of the bottom grain in the first five loading cycles. Scale bars: a 5 nm and j 2 nm.
