Non-Destructive Testing of Particleboard with Ultrasound and Eigenfrequency Methods

Authors: Fredrik Grundström

Abstract

In the production of particleboard, different properties of the board have to be measured in order to keep the board quality within required limits. Non-destructive methods for this purpose include ultra-sonic testing and eigen frequency testing. These methods have been proposed for measuring the strength of the board after pressing, for process control purposes. The ultra sound velocity and eigen frequency have been proved to be good instruments for doing this. The results show that Young’s modulus and bending strength can be predicted with high accuracy with these methods. Internal bond can only be predicted with poor to fair accuracy with normal regression models. The use of multivariate models most often give better predictions of the internal bond. Multivariate models are best suited for complex predictions if the prediction variables are weak.