Anisotropy Characterization of Structural Flakeboards with Ultrasonic Methods

Authors

  • Voichita Bucur

Keywords:

Structural flakeboards, ultrasound, elastic constants, anisotropy, acoustic emission

Abstract

The aim of this research was to study the anisotropic behavior of structural flakeboards using ultrasonic velocity and acoustic emission methods. One full-size board (3,050 x 1,850 x 19 mm) was analyzed for which the orthotropic model was assumed. Ultrasonic velocities of longitudinal and transversal bulk waves were used to estimate the nine stiffnesses. The measurements were performed on specimens of standard size cut from the board. Surface wave velocities were measured on the full-size board along and across the flake alignment direction. Furthermore an acoustic emission technique of breaking 0.5 mm pencil lead on the surface of the specimens was employed. Several parameters of acoustic emission were measured (duration, count number, energy, peak amplitude, rise time) on specimens cut parallel and perpendicular to the direction of flake alignment. The anisotropy was estimated as the ratio of velocities of bulk and surface waves and of acoustic invariants, as well as the ratio of acoustic emission parameters.

References

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Published

2007-06-28

Issue

Number 3 / July 1992

Section

Research Contributions

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