Strain aging based on the dislocation theory

Question

How we illustrate strain aging based on the dislocation theory?

Answer 1

The carbon or nitrogen atoms are significant in yielding procedure since they interact with the dislocations as well as immobilize them. This locking of dislocations is brought about since the strain energy because of the distortion of a solute atom can be relieved if it fits in a structural region where the local lattice parameter approximates to that of the natural lattice parameter of the solute. Such a condition will be brought about through the segregation of solute atoms to dislocations, with great substitution atoms taking up lattice positions in the expanded area, and small ones in compressed region; undersized interstitial atoms will be inclined to segregate to interstitial sites below half-plane. Therefore, where both dislocations and solute atoms are present in lattice, interactions of the stress field can happen, consequential in a lowering of the strain energy of system. This offers a driving force tending to attract solute atoms to disarticulations and if the necessary time for diffusion is permitted, a solute atom “atmosphere” will form around each dislocation.