Pressure-induced transition in titanium metal: a systematic study of the effects of uniaxial stress

Abstract

We investigated the effects of uniaxial stress on the pressureinduced α → ω transition in pure titanium (Ti) by means of angle dispersive x-ray diffraction in a diamond-anvil cell. Experiments under four different pressure environments reveal that: (1) the onset of the transition depends on the pressure medium used, going from 4.9 GPa (no pressure medium) to 10.5 GPa (argon pressure medium); (2) the α and ω phases coexist over a rather large pressure range, which depends on the pressure medium employed; (3) the hysteresis and quenchability of the ω phase is affected by differences in the sample pressure environment; and (4) a short term laser-heating of Ti lowers the α → ω transition pressure. Possible transition mechanisms are discussed in the light of the present results, which clearly demonstrated the influence of uniaxial stress in the α → ω transition.

High-pressure powder x-ray diffraction study of EuVO4

“…High-pressure experiments were performed at room temperature up to 34.7 GPa using 4:1 methanol-ethanol as pressure-transmitting medium (PTM) [33,34].…”

X-ray diffraction study on pressure-induced phase transformations and the equation of state of ZnGa2Te4

“…Ruby grains were loaded with the sample for pressure calibration 18 and a 4:1 methanol-ethanol mixture was used as pressure-transmitting medium. 19,20 Pressure was assumed as the average of the pressure determined from different rubies and the accuracy assumed to be the standard deviation from average. In order to ensure the accuracy of the experiments, special attention was paid to avoiding the sample or the ruby grains bridging with the anvils.…”

Cobalt ferrite nanoparticles under high pressure

“…14 In addition to particle size, there are other facts that could influence the HP behavior of nanocrystals; one is the selection of the pressure-transmitting medium (PTM) used in high-pressure experiments, which may have a strong influence on the physical state of the studied sample. [15][16][17] Therefore, to compare with the most recent HP XRD study, 7 we performed our experiments using the same PTM. However, to compare with the previous studies on CoFe 2 O 4 nanoparticles 11 and to reduce the influence of non hydrostaticity, we limit the maximum pressure to 17 GPa.…”