PROJECTION OF THE SOLIDUS SURFACE OF THE SC-TI-NI SYSTEM IN THE REGION OF TINI-NI-SCNI ALLOYS

Metallographic, x-ray diffraction, electron probe, and differential th ermal analyses are used to study rite interaction of components of TiN i-Ni-ScNi alloys in the Sc-Ti-Ni system at subsolidus temperatures. Th e vertical section between TiNi and ScNi is shown to be quasibinary. N o ternary compounds are observed in the TiNi-Sc-ScNi system. Six singl e-phase, nine two-phase, and four three-phase fields are found on the solidus of the TiNi-Ni-ScNi system. A characteristic feature of the st ructure of alloys of the Sc-Ti-Ni system in the region TiNi-Ni-ScNi ep silon is that the epsilon phase is in equilibrium with the phases base d on TiNi(delta), Ni(gamma), ScNi2(lambda(2)), Sc2Ni(nu), ScNi5(xi), a nd ScNi(delta).