AN INVESTIGATION OF THE B2 PHASE BETWEEN ALRU AND ALNI IN THE AL-NI-RU TERNARY-SYSTEM

An investigation was undertaken to ascertain the extension of the B2 p hase fields from AlNi and AlRu in the Al-Ni-Ru ternary system. The sam ples were are-melted, annealed at 1500 or 1600 degrees C, and examined using optical microscopy, scanning electron microscopy, and X-ray dif fraction. Apparent two-phase samples were deduced as being cored becau se of the indistinct boundary between the phases, and the variation of the component compositions with alloy composition. The presence of an isostructural compound, AlNixRu1-x was indicated by the continuous va riation from AlRu to AlNi in lattice parameter and a smooth trend micr ohardness with a maximum. It is unlikely that both of these trends wou ld have been observed in a system with a two-phase region. (C) 1998 El sevier Science S.A.