On strain-induced dissolution of θ′ and θ particles in Al–Cu binary alloy during equal channel angular pressing

The deformable θ′ particle in Al–Cu binary alloy was found to dissolve more rapidly than the indeformable θ particle due to an additional increasing strain energy accumulated in the deformed θ′ plate as well as an increasing interface energy led by the formation of sub-boundary in the θ′ plate and fragmentation of the particle during equal channel angular pressing (ECAP). The critical radius and the free energy barrier for the strain-induced dissolution of both θ′ and θ particles were calculated.