Is there an effect of dynamic strain aging on dislocation evolution?

Abstract

Herein, we explore the effect of dynamic strain aging (DSA) on dislocation evolution using nanoindentation and transmission electron microscopy (TEM). DSA is primarily manifested as serrations on the load-displacement curves at lower strain rates (10−2 and 10−3 s−1), whereas these serrations are substantially less at higher strain rate (10−1 and 100 s−1). Interestingly, despite variations in strain rates and DSA occurrence, detailed TEM observations beneath the indentations reveal no discernible differences in dislocation density and substructure. The present study indicates that although DSA can increase the gliding resistance of dislocations, it does not affect the evolution of dislocation.

Keywords

• Dynamic strain aging
• transmission electron microscopy
• twinning-induced plasticity steel
• dislocation
• nanoindentation