Bending Properties of Medium-Density Fiberboard and Plywood Obtained by Compression Bending Test

Abstract

Compression bending testing, as described in this article, has been used successfully on various advanced composite materials, such as carbon-fiber reinforced plastics, to compute bending properties. This method might be applicable for several wood-based panels, such as medium-density fiberboard (MDF) and plywood, because they are quite thin, and thus the elastica phenomena can be easily induced. In this study, the bending properties of MDF and Lauan five-ply wood were determined by performing a compression bending test. The validity of the compression bending testing was then examined by comparing these results with the results from flexural vibration tests and three-point bending tests. The compression bending test proved effective for measuring the flexural Young's modulus when the length/thickness ratio was larger than 33 because the test method minimizes deflection caused by shearing force. Nevertheless, it was even less effective when the length/thickness ratio was smaller than 33. It was expected that the test would be more effective than the three-point bending test for measuring proportional limit stress and bending strength because the test specimen is independent of the stress concentration around the loading nose; however, this proved not to be the case for the materials investigated in this study. Thus, further research is still needed to devise ways to more effectively measure the bending properties of the materials tested.