ABSTRACT

This study investigates the influence of wood densities on moduli of rupture and elasticity, internal bond strength, surface soundness and density profiles of light and medium-density three-layered particleboards (PB). Therefore, particles of low and high-density wood species in three-layered PB were combined. Different combinations of beech (Fagus sylvatica L.) as high-density wood species and kiri (Paulownia spp.) as low-density wood species were used as material for the core and surface layers of PBs with target densities of 500 and 650 kg/m³. The results of all tests were influenced by the interaction of two effects: the different densities of the raw materials and the different level of compaction (effectiveness of glue utilization). For target density 500 kg/m³, the compaction of the kiri particles had a greater influence on strength results, than the higher density of the beech raw material. With increasing the target density from 500 to 650 kg/m³, a shift of the dominating effect occurred from effective glue utilization due to compaction towards the effect of the raw material density. The low-density raw material showed minor percentage changes than the high-density raw material.

摘要

这项研究调查了木材密度对轻和中密度三层刨花板（PB）的断裂模量和弹性模量，内部结合强度，表面稳固性和密度分布的影响。因此，将三层PB中的低密度和高密度木材物种结合在一起。山毛榉（Fagus sylvatica L.）作为高密度木材种类和基里（Paulownia spp。）作为低密度木材种类的不同组合被用作PB的芯层和表层材料，目标密度分别为500和650 kg / ³米。所有测试的结果均受以下两种影响相互作用的影响：原材料的密度不同和压实程度不同（胶水利用的有效性）。对于目标密度500 kg / m ³，与较高密度的山毛榉原料相比，基里颗粒的压实对强度结果的影响更大。随着目标密度从500 kg / m ³增加到650 kg / m ³，从压实有效的胶水利用到压实原料密度的影响，产生了主导作用的转变。低密度原料比高密度原料显示出较小的百分比变化。