Effect of moisture content and density on some technological properties of fiberboard

In this study, the effect of moisture content and density of panel on some physical and mechanical properties of fiberboard was investigated. The effect of moisture and density differences on some properties of fiberboard were aimed to be revealed. The test samples were obtained from fiberboards which were divided into three different density (0.590 g/cm3, 630 g/cm3 and 0.680 g/cm3) and moisture contents (6%, 9% and 12%) groups. Within the scope of the study, physical properties such as water absorption and thickness swelling and mechanical properties such as bending strength, modulus of elasticity, internal bond strength, Janka hardness and screw holding capacity were determined. The physical and mechanical properties of the boards with different moisture and density values differed significantly. For instance, the internal bond strengths were determined as 0.34 N/mm2, 0.39 N/mm2 and 0.62 N/mm2 in the low, medium and high density groups, respectively. Respective values for moisture content groups were found 0.52 N/mm2, 0.45 N/mm2 and 0.38 N/mm2, respectively. Furthermore, the screw holding capacity which is important strength for fiberboard were determined as 15.3 N/mm2, 18.8 N/mm2 and 25.3 N/mm2 in the low, medium and high density groups, respectively. And respective values for moisture content groups were found as 19.8 N/mm2, 20.1 N/mm2 and 19.4 N/mm2, respectively. In the samples belonging to the same moisture group, high mechanical properties at low moisture content and low mechanical properties at high moisture content were obtained. Research results revealed that the mechanical properties increased in parallel with the increase in density. Physical and mechanical properties of MDF boards change as the board density increases. Generally, as the board density increased, all mechanical properties increased. However, with the increase in moisture percentage, the mechanical properties of the boards decreased.