Superlattice dislocations in the L1₂ordered structure of Cu₂NiZn

Superlattice dislocations in L12 ordered alloys and in alloys containing L12 ordered precipitates

“…5). Recently, we determined the long-range zinc ordering S" in Cu2NiZn as a function of the annealing temperature by single-crystal neutron diffraction [6]. The long-range order parameter 8" is 0025-5416/86/$3.50 © Elsevier Sequoia/Printed in The Netherlands obtained by taking the measured intensities of the superreflections relative to the corresponding intensities of the fundamental reflections and averaging over equivalent reflections [ 7].…”

“…Recently, we determined the long-range zinc ordering S" in Cu2NiZn as a function of the annealing temperature by single-crystal neutron diffraction [6]. The long-range order parameter 8" is 0025-5416/86/$3.50 © Elsevier Sequoia/Printed in The Netherlands obtained by taking the measured intensities of the superreflections relative to the corresponding intensities of the fundamental reflections and averaging over equivalent reflections [ 7]. From the single-crystal neutron diffraction study we concluded that, below the first critical temperature T~ of about 774 K, a modified L12 structure exists, in which zinc atoms occupy one of the four interpenetrating single cubic sublattices while copper and nickel are still randomly distributed over the remaining three sublattices.…”