Internal Friction and Elastic Constants of Sintered Titanium

Published

December 1, 1996

Author(s)

H M. Ledbetter, Martin Dunn, Sudook A. Kim

Abstract

Using a Marx-oscillator standing-wave resonance method, we measured the internal friction {quaternary}^-1^ of sintered titanium containing up to 26 volume-percent voids (c). The surprising {quaternary}¹ versus-c curve shape, an exponential increased, lead us to remeasure {quaternary}^-1 -versus-c by acoustic-resonance spectroscopy, which gave similar results. We hypothesized that both void shape and void size change with c. For the void shape, we confirmed this hypothesis by measuring longitundinal and transverse sound velocities {nu₁} and comparing them with Mori-Tanaka model predictions. As c increases from 0 to 0.26 effective void shape changes from near spherical to oblate spheroidal with an aspect ratio near 0.05. Optical microscopy confirmed the void-size change. We outline a model based on wave-scattering theory that explains the observed {quaternary}^-1 -c behavior. Increased particle size with increased c provides the dominant factor for the exponential {quaternary}^-1 increase.

Citation

Journal Dephysique

Volume

6

Pub Type

Journals

Keywords

elastic constants, internal friction, titanium, voids

Citation

Ledbetter, H. , Dunn, M. and Kim, S. (1996), Internal Friction and Elastic Constants of Sintered Titanium, Journal Dephysique (Accessed December 1, 2024)