Experimental Investigation of the Mo–Ti–Zr Ternary Phase Diagrams

In this work, the phase diagrams of the Mo–Ti–Zr ternary system were determined by means of X-ray diffraction, optical microscopy, and electron probe microanalysis. Two isothermal sections of the Mo–Ti–Zr ternary system at 900 and 1100 °C were experimentally established. There are three two-phase regions and one three-phase region at both isothermal sections. The existence of the three-phase region (β1 + Laves + β2) at 900 and 1100 °C indicates that the β phase (bcc solid solution) separates into two phases, i.e. Mo, Ti rich solid solution β1 and Ti, Zr rich solid solution β2. No ternary compounds were detected. The maximum solubilities of Ti in the Laves phase were found to be 19.3 at.% at 900 °C and 18.3 at.% at 1100 °C, respectively. The liquidus projection and reaction scheme of the Mo–Ti–Zr system were also presented based on the present experimental work and literature information.