Localized Properties in Flakeboard: A Simulation Using Stacked Flakes
Keywords:Flakeboard, vertical density distribution, strength, thickness swell, heat transfer
AbstractHeat transfer, vertical density distribution, bond strength, and dimensional stability were determined for columns of trembling aspen wood flakes pressed to simulate the density variation found within a flakeboard mat. Variables studied included: 1) the number of wood flakes in each column, 2) face flake moisture content, and 3) press closing time. The face, intermediate, and core layers of the resulting flake assemblies were evaluated in terms of the heat transfer occurring during pressing, their vertical density distribution, shear bond strength, and dimensional stability. More rapid heat transfer to the core of the flake assemblies was generally associated with shorter press closing times, higher moisture content face flakes, and lower initial numbers of flakes. Face densities were greatest for the shorter press closing time and low moisture content face flakes. Relative density differences between face and core layers were greatest for low numbers of flakes. Greatest strengths were found at the face layer and followed the vertical density distributions. Press closing time had no effect on strength. Face flake moisture content affected only the strength of the face and intermediate layers of the flake assembly composed of the greatest number of flakes. Thickness swelling trends closely followed the vertical density distributions.
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