Prediction of ultrasonic properties from grain angle

Abstract

The ultrasonic properties of rubber wood were evaluated in three main symmetry axes – longitudinal (L), radial (R) and tangential direction and also at an angle rotating from the symmetry axes at different moisture content. The ultrasonic velocity were determined with a commercial ultrasonic tester of 45 kHz pulsed longitudinal waves. The experimental results were compared with the predicted value using some empirical formula such as Hankinson, Osgood and Jacoby equation. For LR and LT rotations, the predicted ultrasonic velocity using Hankinson and Osgood equations are in close agreement with the measured value for almost all moisture content. Jacoby equation predicted well only at an angle greater than 50°. In RT rotation, all these equations can be used for the prediction of ultrasonic velocity of rubber wood. In RT rotation, the value of the exponent for Hankinson and Osgood are higher compared to LR and LT rotations. Whereas in the Jacoby equation it was found to be lower.

Citation

Kabir, M.F. 2001. Prediction of ultrasonic properties from grain angle. Journal of the Institute of Wood Science. 15(5): 235-246.