TITLE:
TEM Characterization of Dynamic Recrystallization in TiB2 Particles after Hypervelocity Impact
AUTHORS:
Q. Guo, J. F. Li, L. L. Hou, D. L. Sun
KEYWORDS:
Impact, TiB2 Particle, Dynamic Recrystallization
JOURNAL NAME:
Microscopy Research,
Vol.2 No.3,
July
31,
2014
ABSTRACT: Characteristic of dislocations and dynamic recrystallization in TiB2 particles associated with hypervelocity impact craters in 65 vol.% TiB2/Al composite were investigated by transmission electron microscopy (TEM). As high temperature due to hypervelocity impact can make the dislocation climb, a bunch of vacancies were generated and then gathered to form vacancy slice, finally formed dislocation rings. In addition, by climbing, edge dislocations rearranged themselves into wall vertical with slip plane, which finally forms sub grain boundary. Moreover, big angle grain boundaries were observed, which demonstrates that dynamic recrystal grains were formed in impacted TiB2 particles. As a result, deformation behavior of TiB2 particles in 65 vol.% TiB2/Al composite under hypervelocity impact includes generation of dislocation, slip and climb of dislocation, and dynamic recrystallization.