FFT-Estimation of Fiber Orientation on Wood Fiberboard
Murata Koji; Fujita Minoru
Abstract:The property of many engineering woods depends on the shape and orientation of their elements. This paper describes an attempt to estimate the 3-dimensional fiber orientation in insulation fiberboard (IB). Serial sections of IB were sliced off at every 50mm parallel to the board plane by a sliding microtome. Before sectioning, the specimen was embedded in epoxy resin and cured. Then, it was boiled in water for several hours to make the resin moderately soften. The orientation values were calculated on 2-dimensional Fourier transform image analysis. Analytical value indicates that fibers near the both surfaces orient to machine direction and the orientations decrease on inner plane. Section thickness was shown to affect the orientation values. The value was underestimated on a too thin section, because fibers are fragmented. On the other hand, obscure image of overlapping fibers on a too thick section gave also underestimated value. Some ideas are proposed to search for appropriate thickness. Key Words:wood fiberboard, orientation analysis, Fourier transform, fiber orientation