Measurement and Analysis of Vibration Damping Capacity of Lotus-Type Porous Magnesium

Abstract:

Lotus-type porous magnesium was fabricated by unidirectional solidification of the melt dissolving hydrogen in a high-pressure mixture gas of hydrogen and argon. The damping constant
of porous magnesium with various porosities was measured by the hanging excitation method. The damping constant was defined as α=log (xn/xn+1)/
T, where xn and xn+1 are the successive amplitude values of the damping wave, and
T is the damping time. The frequency-amplitude dependence curve was obtained by Fast Fourier Transform analysis. The damping time of the lotus-type porous magnesium was observed to be shortened greatly compared with non-porous metals and porous copper. Moreover, the damping constant of the lotus-type porous magnesium was calculated by the damping amplitude.

• Periodical: Materials Science Forum (Volume 512)
• Pages: 325-330
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.512.325
• Online since: April 2006
• Authors: Zhen Kai Xie, Soong Keun Hyun, Yosiyuki Okuda, Hideo Nakajima
• Keywords: Frequency, Hydrogen, Magnesium, Porosity, Vibration Damping

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