Mechanical Spectroscopy of the Formation of Quasicrystalline Order in Rapidly Quenched Ti- and Zr-based Alloys

Abstract

ABSTRACTThe development of quasicrystalline (qc) order from different initial states (amorphous, nano- or poly-qc) was studied in rapidly quenched Ti-Zr-Ni(-Ag), Ti-Zr-Fe, and Zr-Cu-Ni-Al alloys by means of mechanical spectroscopy (vibrating-reed technique), including both the irreversible changes of Young's modulus and the Snoek-type relaxation peak of absorbed hydrogen as a probe, which are obviously sensitive to quite different types of ordering processes. The strongest annealing effects on Young's modulus were found for extreme nano-qc material at the amorphous limit, whereas order-induced narrowing of the hydrogen peak occurs only at comparatively larger grain sizes. More important differences in the properties of the hydrogen peak are found between quasicrystals of different compositions. The results are briefly discussed with respect to their implications for the amorphous-to-quasicrystalline transition and for the experimental distinction between different types of icosahedral quasicrystalline order.