Interfacial strain relief by periodic dislocation doublets emerging from rotationally related orientation relationships of Y4Zr3O12 dispersions in ferrite matrix

Abstract

The trigonal/bcc orientation relationships (ORs) and their likelihood of occurrence are extensively studied using dispersed Y4Zr3O12nano-precipitates in bcc Fe matrix by means of transmission electron microscopy, image simulations, and a crystallographic model. Two orientation relationships related by a rotation:[1-20]||[111] with (21-2)||(-110) and [1-20]||[111] with (00-3)||(-110), are established and periodic arrays of misfit dislocation doublets are identified at the strained interface in (110) for both ORs. Further eighteen energetically feasible ORs in Y4Zr3O12/bcc system are deduced by combining stereographic projections, which include the two predominant ORs in this study and other ORs in literature. The orientation relationship which generates the interface with a minimum number of dislocation doublets is the most frequent.