Mechanical Properties of MDF as a Function of Density and Moisture Content

This study examined the effect of medium density fiberboard (MDF) density and moisture content on MDF moduli of elasticity E 1 , E 3 , shear modulus, G 13 , and Poisson's ratios v 12 and v 13 . The relation of all parameters with density was determined from MDF panels without density profile with average density levels of 540 kg/m 3 , 650 kg/m 3 , and 800 kg/m 3 . The relation with moisture content was determined from specimens conditioned to 50%, 65%, and 80% relative humidity. Panel E 1 , E 3 , and G 13 increased with density increase and decreased with moisture conent increase. At each nominal density level, the values of E 1 were much higher than the values of G 13 , which in turn were higher than the values of E 3 . The effect of density and moisture content on the Poisson's ratios was not significant.