Isothermal sections at 1400, 1100 and 900°C of the Ti–Dy–Sn system below 40at.% Sn

Abstract

Abstract By the methods of X-ray diffraction, SEM and electron probe microanalysis, phase equilibria in the Ti–Dy–Sn system below 40 at.% Sn at temperatures 1400, 1100 and 900 °C were studied. The isothermal sections at 1400, 1100 and 900 °C were constructed. It was shown that the ternary compound Ti 4.2−4.3 Dy 0.8−0.7 Sn ⩽ 3 ( τ ) is stable at these temperatures. At 1400 °C the liquid phase is present in the system. The isothermal section at this temperature is characterized by the three-phase regions L + (βTi) + (Dy 5 Sn 3 ), (βTi) + (Тi 3 Sn) + (Dy 5 Sn 3 ), (Ti 3 Sn) + τ + (Dy 5 Sn 3 ), (Ti 3 Sn) + τ + (Ti 2 Sn) and (Ti 2 Sn) + τ + (Ti 5 Sn 3 ) and appropriate two-phase fields. At 1100 and 900 °C the liquid phase is absent, instead the three-phase field (βTi) + (αDy) + (Dy 5 Sn 3 ) appears. Other three-phase fields exist at all the temperatures studied. The isothermal sections at 1100 and 900 °C by their character are similar to the solidus surface.