Atomic arrangements of long-period superstructures in Au-24.5 at.% Cd alloy with the basic h.c.p. structure have been investigated by high-resolution electron microscopy. The alloy shows one-dimensional or two-dimensional long-period superstructures in the close-packed plane with a 6H stacking sequence, depending on heat treatments. It is shown that the two-dimensional incommensurate superstructure with a period larger than 9a0 is composed of domains of the hexagonal commensurate structure (M = 9) separated by the antiphase-boundary zone in which 33/2 a0 × 2a0 × 3c0 orthorhombic structure is formed (a$-04/, c0 being the lattice parameters of the h.c.p. structure).
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)