Microcompression and cyclic deformation behaviors of coaxial copper bicrystals with a single twin boundary

Controllable fatigue cracking mechanisms of copper bicrystals with a coherent twin boundary

“…The fatigue cracks nucleate preferentially along the primary SBs similar to single crystals 3,5 . Besides, some SB cracks exist in the grain interior and some SB cracks even pass through the TB as detected before 23,24 . As exhibited in Fig.…”

“…It can be seen from Fig. 2a that the SBs belonging to the S1 slip systems appear and no secondary SB is found 23,24 . The SBs can transfer across the TB with mirror symmetric relationship which is consistent with the schematic plot in Fig.…”

“…When the TB is parallel to the loading direction, the two component grains have the same crystallographic orientation and same Schmid factor distribution. The slip systems with the highest Schmid factor in both the component grains are always the ones whose slip direction is parallel to the TB plane with the slip plane intersecting with the TB 23 as depicted in Fig. 1c.…”

Cyclic bending experiments on free-standing Cu micron lines observed by electron backscatter diffraction

“…Microcompression experiments on single-crystalline and bicrystalline samples [53] revealed that the types of grain boundary and dislocations strongly influence the deformation behavior of a sample at the micron scale: samples with a P 3 (1 1 1) boundary showed a comparable mechanical response to single-crystalline samples, as for specific glide systems screw dislocations can cross-slip through a certain kind of well-oriented twin boundary. Samples with a large angle grain boundary showed strong hardening in microcompression studies as dislocations accumulate on the impassable grain boundary [53,54].…”

Difference in fatigue cracking behaviors of Cu bicrystals with the same component grains but different twin boundaries

“…All the fatigue specimens were ground and electropolished carefully before cyclic deformation. Symmetrical push-pull tests were performed with an Instron E1000 testing machine at increased shear stress amplitude at room temperature in air [20,21]. A triangular wave with a frequency of 1 Hz was used.…”