INTERNAL-FRICTION IN CU-AL-NI CRYSTALS IN MARTENSITIC PHASE AND DURING TEMPERATURE-INDUCED MARTENSITIC-TRANSFORMATION

Temperature and oscillatory strain amplitude dependences of the ultras onic amplitude-dependent internal fiction and oscillatory anelastic st rain at temperatures 6.5-300K have been studied in Cu-Al-Ni single cry stals in martensitic phase. An anomalous behaviour of the amplitude de pendent internal friction and effective Young modulus was revealed in quenched crystals: the amplitude dependent internal friction decreases with temperature increase at all temperatures and strain amplitudes i nvestigated, and the Young modulus increases notably with temperature from 70 to 200K. The anomalies in the ADIF and effective Young modulus behaviour are attributed to peculiarities of dislocation dynamics.