تقرير
Observation of a metastable intermediate during solid-solid phase transformation in response to rapid compression
| العنوان: | Observation of a metastable intermediate during solid-solid phase transformation in response to rapid compression |
|---|---|
| المؤلفون: | Armstrong, Michael R., Radousky, Harry B., Austin, Ryan A., Stavrou, Elissaios, Zong, Hongxiang, Ackland, Graeme J., Brown, Shaughnessy, Crowhurst, Jonathan C., Gleason, Arianna E., Granados, Eduardo, Grivickas, Paulius, Holtgrewe, Nicholas, Lee, Hae Ja, Li, Tian T., Lobanov, Sergey, McKeown, Joseph T., Nagler, Robert, Nam, Inhyuk, Nelson, Art J., Prakapenka, Vitali, Prescher, Clemens, Roehling, John D., Teslich, Nick E., Walter, Peter, Goncharov, Alexander F., Belof, Jonathan L. |
| سنة النشر: | 2018 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Materials Science |
| الوصف: | In order to probe the mechanism of solid-solid phase transformations, we have applied ultrafast shock wave compression (120 picosecond duration) and ultrashort (130 femtosecond) x-ray diffraction at the Linac Coherent Light Source (LCLS) to probe the compression-induced phase transition pathway in zirconium. Surprisingly, rather than transform from alpha-Zr to the more disordered hex-3 equilibrium omega-Zr phase, in its place we find the formation of a non-equilibrium body-centered cubic (bcc) metastable intermediate. Theoretically hypothesized for several decades, this bcc intermediate state has now been found to be dynamically stabilized under uniaxial loading at sub-nanosecond timescales. Molecular dynamics simulations of shock-wave propagation in zirconium predict this transformation via the dynamical intermediate state. In contrast with longer timescale experiments where the phase diagram alone is an adequate predictor of the crystalline structure of a material, our recent study highlights the importance of metastability and time-dependence in the kinetics of phase transformation at extreme conditions. |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/1808.02181 |
| رقم الأكسشن: | edsarx.1808.02181 |
| قاعدة البيانات: | arXiv |
كن أول من يترك تعليقا!