Abstract
The crystal structure of electrodeposited nickel with a preferred orientation was investigated by electron microscopy and electron diffraction. A number of twins occurred frequently in all of the deposits having (100), (110), (210) and (211) preferred orientations, respectively. Particularly in those with the (211) orientation, twin pyramids of a two-fold symmetry with a twin plane perpendicular to the substrate surface were observed. An extra diffraction spot arising from deposits with the (211) orientation has been considered to be due to a hexagonal close-packed phase of nickel or cobalt coexisting with a face-centered cubic phase. However, since the extra spot arises from the effect of kinematical double diffraction at boundaries between matrix and twin, the previous interpretation of this extra spot in terms of the presence of a hexagonal close-packed metal is not justifiable. It was considered that in the above four preferred orientations the deposits would not be chemically stable and there is no great difference in chemical activity among the deposits with different preferred orientations.
