On the hardening in modulated structure

Abstract

Hardening in modulated structure is evaluated using the periodic approximation. The critical shear stress incrementΔτ due to the periodic structure is calculated in the constant line energy approximation. The results are applicable to any periodic structure (concentration waves must be neither homophase nor symmetric) exerting on the dislocation local glide forces with an amplitude smaller thanγβ (γ denotes the line energy of corresponding straight dislocation directed along the concentration variations with the wave vectorβ). In the zero approximation, the critical forceΔτb is then simply the glide force on the straight dislocation averaged along its length in its most hardened position.