2. Mechanisms of isothermal relaxation

Only a brief description of the relaxation mechanisms will be given in the case of a relaxation test with the initial relaxation stress above the yield stress, σ ₀ > σ _E [2] . During loading, dislocations are created and propagate. How do these dislocations evolve during relaxation?

Plastic strain ε _p is related to the density of mobile dislocations ρ _m by the Bailey-Orowan relation :

where α is a geometric...