Isothermal section at 500 degrees C of the Ho-Ni-Ti ternary system

By means of X-ray powder diffraction (powder XRD), differential thermal ana lysis (DTA), metallographic micro-analysis and electron probe microanalysis (EMPA), the isothermal section at 500 degrees C of the Ho-Ni-Ti ternary sy stem was determined. This section constists of 14 single-phase regions, 25 two-phase regions and 12 three-phase regions. The existence of 11 binary co mpounds was confirmed. No Ho-Ti binary compound was found. No ternary compo und was found. The maximum solid solubilities of Ti in beta (alpha-Ni), sig ma (Ho2Ni17), omega (HoNi5), phi (Ho2Ni7), chi (HoNi3), delta (HoNi2) at 50 0 degrees C are 7.8, 2.8, 3.0, 1.1, 3.2 and 5.0 at. % respectively.