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Pressure-induced alpha-to-omega transition in titanium metal: A systematic study of the effects of uniaxial stress

Daniel Errandonea·Y. Meng·M. Somayazulu·D. Hausermann
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Abstract

We investigated the effects of uniaxial stress on the pressure-induced alpha-to-omega 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 a and w phases coexist over a rather large pressure range, which depends on the pressure medium employed; (3) the hysteresis and quenchability of the w phase is affected by differences in the sample pressure environment; and (4) a short term laser-heating of Ti lowers the alpha-to-omega transition pressure. Possible transition mechanisms are discussed in the light of the present results, which clearly demonstrated the influence of uniaxial stress in the alpha-to-omega transition.

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Daniel Errandonea, Y. Meng, M. Somayazulu, D. Hausermann. 2004-04-26. Pressure-induced alpha-to-omega transition in titanium metal: A systematic study of the effects of uniaxial stress. https://doi.org/10.1016/j.physb.2004.10.030

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