Phonons in Ni₃₁Dy₆₉ Glass

Abstract

The effective interatomic potential in Ni,,Dy,, glass is obtained with the experimental structure factor S(Q). This potential is compared with those computed using Percus-Yevick (PY) and hypernetted chain (HNC) approximations. A theory of phonons in amorphous solids is employed to compute the eigenfrequencies of the longitudinal and transverse phonon modes with these diffcrcnt potentials and the results are compared with each other. The elastic and thermodynamic properties of this glass are also studied using the longitudinal and transverse sound velocities estimated from the slope of the long-wavelength limit of the dispersion relations.') Jaipur 302004, India.

Phonon Dispersion in Amorphous Ni-Alloys

“…The present results of Ni 33 Y 67 glass are found lower in line with other theoretical data [1]. Also the present outcome of Ni 50 Zr 50 glass shows lower results in comparison with the theoretical reported data [2].…”

“…The presently obtained pair potentials of Ni 33 Y 67 glass are shown in Fig. 1b along with the other such theoretical results [1,16]. The first zero position of pair potentials at r = r 0 due to all screening functions occurs at r 0 ≈ 3.95 a.u.…”

“…But the well width increases compared to H-screening. It is observed that well depth of presently computed pair potentials is shifted towards the left and is also high as compared to the results of Arun Pratap et al [1] and Hausleitner-Hafner [16]. The presently generated pair po-tentials of Ni 36 Zr 64 glass are displayed in Fig.…”

“…And only recently there has been an explosion of interest to these studies as more promising materials are produced in the amorphous form. The range of applications of metallic glasses is vast and extends from the common window glass to high capacity storage media for digital devices [1][2][3][4][5][6][7][8].…”

“…Another four metallic glasses such as Ni 33 Y 67 , Ni 36 Zr 64 , Ni 50 Zr 50 , and Ni 60 Nb 40 are the members of transition metallic (TM-TM) glasses. The phonon dynamics of Ni 33 Y 67 glass was studied by Arun Pratap et al [1], by Hubbard-Beeby (HB) [3], and Takeno-Goda (TG) [4] approaches. The vibrational dynamics of Ni 50 Zr 50 glass has been studied by Gupta et al [2] using…”