Ultrasonic characteristics of porous Pd42.5 Cu30 Ni7.5 P20 glassy alloys

Mikio Fukuhara, Takeshi Wada, Akihisa Inoue

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8 Citations (Scopus)


Using ultrasonics, the acoustic characteristics of porous Pd42.5 Cu30 Ni7.5 P20 glassy alloys were examined in terms of complex elasticity. Bulk modulus (K) and Lam̀ parameter (λ) decrease in a parabolic manner as porosity increases, while Young (E) and shear (G) moduli decrease linearly. Consequently, the order of K>λ>E>G, which is monopolistically characterized by nonporous glassy alloys, changes to the order of E>K>λG at 58% porosity. The decrease in Poisson's ratio and the increase in GK ratio up to 58% porosity indicate crystallinelike characteristics that resist three-dimensional volume-nonpreserving deformation. An increase in porosity induces frequency convergence for longitudinal waves and an increment of the imaginary parts in the complex waves. The viscoelasticity of the porous glassy alloys is predominated by shear motion. In contrast to the continuous increment in dilational damping, the porosity-dependent increment in shear damping could be elucidated based on the accumulation of strains induced by the formation of pores.

Original languageEnglish
Article number083502
JournalJournal of Applied Physics
Issue number8
Publication statusPublished - 2007

ASJC Scopus subject areas

  • Physics and Astronomy(all)


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