Atomic structure of a {110} Zr/ZrN interface

Abstract

Investigation of the atomic structure of a micrometer-level faceted (011) Zr/ZrN interface by high-resolution transmission electron microscopy (HRTEM), diffraction contrast imaging, and near-coincidence-site (NCS) atomic modeling shows that it is a type-3 incoherent interface (i.e., it has a high-index orientation relationship with a low-index interface plane in only one phase). The HRTEM images show that the interface is rougher than similar type-3 incoherent {111}ZrN interfaces previously analyzed, indicating that there may be both atomically faceted and rough type-3 incoherent interfaces. Nanofacets form at the interface even though the NCS matching is not good, suggesting that micrometer-level faceting (including nanofaceting) might be the dominant factor in determining the interface plane of an atomically rough, type-3 incoherent interface, and not NCS matching. Electron energy-loss spectrometry and energy-filtered TEM images show that the composition changes abruptly at the {110}ZrN interface, in accord with the structural transformation.