PHONON-DISPERSION RELATIONS OF PREMARTENSITIC BETA(1)-PHASE IN AUZN ALLOYS

Phonon dispersion relations in AuZn alloys were measured at 293, 150 a nd 110 K. The [110]TA(1) branch had a dip and the phonon energy decrea sed with decreasing temperature. The energy of the [111]LA branch incr eased with decreasing temperature. The structure of the martensite was proved to be trigonal. The martensitic transformation in the AuZn bet a-phase alloy is thought to occur by a (110) [1 $($) over bar$$ 10] sh ear through the same mechanism as the zeta-martensite in AuCd alloys.