The segregation of interstitial atoms around the dislocation and formation of the Cottrell atmosphere lead to blockage of dislocations motion.
However, the last action is often not considered as an invariable solution for eliminating the yield point elongation in mild steels because after aging, the interstitial atoms pine the dislocations and form the Cottrell atmosphere [3, 4].
The high tensile load produces plastic flow due to movement of edge dislocation with Cottrell atmosphere
such that the edge dislocation separates from the enclosed interstitial solutes.
The results showed an area shaped like a tube that was rich in boron atoms--a Cottrell atmosphere surrounding a dislocation.
Now, for the first time, scientists have obtained three-dimensional images of these clouds of additive atoms, known as Cottrell atmospheres.