Strengthening Mechanisms in Al–Li Alloys Containing Coherent Ordered Particles

Abstract

Strength of Al–Li alloys containing Ll₂ ordered δ′-particles have been discussed on the basis of observed behavior of dislocations, taking into account various resistances to dislocation motion in the alloys. The measured yield strength and the observed arrangements of deformation induced dislocations are successfuly explained in terms of the dislocation-particle interaction theories. Main contributions to the strength of the alloys come from the energy of antiphase boundaries and the friction stresses in the ordered particles and in the matrix.