Anomalous phonon behavior in the high-temperature shape-memory alloy Ti50Pd50-xCrx
| Title | Anomalous phonon behavior in the high-temperature shape-memory alloy Ti50Pd50-xCrx |
| Publication Type | Journal Article |
| Year of Publication | 2007 |
| Authors | Shapiro SM, Xu GY, Winn BL, Schlagel DL, Lograsso T, Erwin R |
| Journal Title | Physical Review B |
| Volume | 76 |
| Pages | 054305 |
| Date Published | Aug |
| Type of Article | Article |
| ISBN Number | 1098-0121 |
| Accession Number | ISI:000249155100067 |
| Keywords | electron-microscopy, phase, premartensitic phenomena, TI50PD42CR8, TRANSFORMATION |
| Abstract | Ti50Pd50-xCrx is a high-temperature shape-memory alloy with a martensitic transformation temperature strongly dependent on the Cr composition. Prior to the transformation, a premartensitic phase is present with an incommensurate modulated cubic lattice with wave vector of q(0)=(0.22,0.22,0). The temperature dependence of the diffuse scattering in the cubic phase is measured as a function temperature for x=6.5, 8.5, and 10 at. %. The lattice dynamics has been studied and reveals anomalous temperature and q dependences of the [110]-TA(2) transverse phonon branch. The phonon linewidth is broad over the entire Brillouin zone and increases with decreasing temperature, contrary to the behavior expected for anharmonicity. No anomaly is observed at q(0). The results are compared with first principles calculation of the phonon structure. |
| DOI | 10.1103/PhysRevB.76.054305 |
| Alternate Journal | Phys. Rev. B |
