Abstract

The dispersion relation of [110] TA 1 phonon ( e //[1\bar10]) of β 1 -phase Cu 69.2 Al 25.4 Ni 5.4 was measured extensively at 261, 295 and 372 K by neutron scattering technique. It was found that the dispersion surface of the transverse acoustic mode has a pronounced valley along the [110] axis. The temperature dependence of the phonon energy shows a partial softening of the phonon mode. An anomalous dip of the dispersion curve was observed around q =(2/3) q max on the [110] axis. Interplaner force-constant analysis revealed that the lattice dynamics of the crystal indicates dual instabilities both to the 2H and 18R type martensites. Quasielastic scattering was investigated on and in the vicinity of the [110] axis. Peaks attributable to the 2H and 18R martensites were observed as functions of temperature, which also indicates that 2H and 18R are competing.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.