Phonon dispersion relations of premartensitic β1-phase in AuZn alloys

Abstract Phonon dispersion relations in AuZn alloys were measured at 293, 150 and 110 K. The [110] TA 1 branch had a dip and the phonon energy decreased with decreasing temperature. The energy of the [111] LA branch increased with decreasing temperature. The structure of the martensite was proved to be trigonal. The martensitic transformation in the AuZn β-phase alloy is thought to occur by a (110) 110 shear through the same mechanism as the ζ -martensite in AuCd alloys.