<110> Dislocation Junction Formation via the Coalescence between Nanoscale 1/2<111> Prismatic Dislocation Loops in Iron

Abstract

Accurate knowledge of dislocation reactions is crucial for understanding and controlling the macroscopic mechanical properties of α-iron and its alloys. A dislocation reaction: 1/2[111] + 1/2[11 1]→[110] has never been observed. However, using in-situ transmission electron microscopy, we demonstrate that the two nanoscale 1/2 <111> prismatic dislocation loops that undergo 1D glide motion approach and collide with each other to form a "high-energy" [110]-dislocation junction. This anomalous reaction cannot be understood within the framework of the elasticity.