Experimental constraints on the phase diagram of elemental zirconium

Shear-driven instability in zirconium at high pressure and temperature and its relationship to phase-boundary behaviors

“…For example, Zhao et al [18] probes the phase diagram up to 17 GPa and 1000 K, resulting in x-ray determined equations of state for all (α, ω, and β) phases known to exist in this range. Similar work has been published by Zhang et al [7] wherein they explore the high pressure and temperature phase boundaries using x-ray diffraction. Other similar studies have been reported, but inspection of typical equation of state forms can illustrate the limitations of such a study.…”

“…While such behavior may be expected, due to softening with increasing temperature, this feature shows a degree of extreme localization suggesting , and adiabatic bulk modulus (c), all in GPa, are shown over the P -T range explored through this work. Overlaid on these plots are proposed phase boundaries from work by Wenk [17] and Zhang [7,27] and colleagues. The actual data points measured are plotted in (a) along with the other information.…”

“…In these plots, the main points of interest are clearly seen, as described in the text. The left and right branches of the results from Zhang et al's paper [7] have been determined as follows. The left branch is directly from the phase boundaries reported (Figure 4 of their paper).…”

“…However, the actual phase boundary is quite difficult to pin down, as evidenced by many works [5,7,17,18,[23][24][25][26][27][28][29], where the prime difficulty is wide α − ω coexistence. Other interesting features exhibited include high pressure-temperature amorphous phases [7,30] and phase boundaries that exhibit possible kinks [7,27] (i.e., change from positive to negative dT/dP phase boundary slope). This report presents high pressure-temperature studies on zirconium in the range up to 7 GPa and 1400 K using UT and simultaneous x-ray diffraction and radiography.…”

Exploring Thermal and Mechanical Properties of Selected Transition Elements under Extreme Conditions: Experiments at High Pressures and High Temperatures

“…Volumes of hcp (α) phases of Ti and Zr have been extensively measured at various high pressure and temperature conditions and have been compiled from several recent sources. Some data is available on volumes of the ω and β phases of Ti and Zr however there is some discrepancy between different sources about the placement of the phase diagram boundaries between these phases at very high pressures and temperatures (Rao and Menon, 1973;Xia, Duclos, et al, 1990;Greeff, 2005;Zhang et al, 2005;Zhao et al, 2005;Lu, Selleby, et al, 2005b;Pecker et al, 2005;Liu, Li, et al, 2008;Tian, Sun, Yang, et al, 2008;Tian, Sun, Zhang, et al, 2008;Pérez-Prado and Zhilyaev, 2009;Speirs, n.d.). Several conflicting sources have reported a discovery of novel ultra-high pressure phases in Ti, however there have not been any attempts to determine their high temperature properties (Vohra and Spencer, 2001).…”