The interaction between extended dislocations and antiphase domain boundaries - I: superpartial separation and the yield stress

The interaction between an extended superdislocation in an ordered structur e and an antiphase domain boundary (APB) has been analysed. In contrast to previous treatments (Cottrell AH. Relation of properties to microstructure. ASM Monograph 1954. p. 131; Ardley GW. Acta Metall 1955;3:525) we include the effects of (i) the small strip of perfect crystal within an extended di slocation straddling an APDB and (ii) the ledge in an APDB which has been c ut by a dislocation. We also revisit the concept of APDB thickness'. The ne w analysis leads to a more marked variation of superpartial separation with domain size than previously calculated and also predicts a variation of yi eld stress with domain size which is in better agreement with experiment th an are previous calculations. (C) 2001 Elsevier Science Ltd. All rights res erved.