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›› 1987, Vol. 23 ›› Issue (2): 182-190.

• 问题讨论 • 上一篇    下一篇

白杨木材横纹压缩流变性能Ⅰ.粘弹性

王培元   

  1. 中国林业科学研究院木材工业研究所
  • 收稿日期:1985-04-11 修回日期:1900-01-01 出版日期:1987-05-25 发布日期:1987-05-25

THE RHEOLOGICAL BEHAVIOUR OF POPLAR WOOD IN COMPRESSION PERPENDICULAR TO GRAIN I .VISCOELASTICITY

Wang Peiyuan   

  1. Research Institute of Wood Indusfry, Te Chinese Academy of Forestry
  • Received:1985-04-11 Revised:1900-01-01 Online:1987-05-25 Published:1987-05-25

摘要: 当白杨木材受横纹压缩时,各种性质的变形彼此重叠交织而难以分辨。然而用参数分离法研究白杨木材横纹压缩流变性能看来是有效的。本研究用上述方法考察各种变形在试样分别处于不同温度和含水率,以及有蒸汽通过时的流变表现,其目的在于了解刨花板热压过程和板的物理性能之间的关系。其粘弹性所反映出的特征很像三维网状结构高聚物分子的力学特性。当试样为绝干时,随着温度的升高(20—105℃),弹性柔量及推迟弹性柔量只有很少量的增加。当试样含水率提高时,随着温度的升高,则其弹性柔量及推迟弹性柔量增加很多。当试件处于室温时,只提高其含水率,则其弹性柔量及推迟弹性柔量虽有较明显的增加,但幅度并不大。当有蒸汽通过试样时,弹性柔量有大幅度提高。

Abstract: It is quite difficult to identify the various kinds of deformation in the apparent mechanical behaviour of poplar wood as loaded perpendicular to its grain. However, by means of separating the theological parameters, it was found somewhat effective in studing of the theological behaviour of poplar wood under compression perpendicular to its grain. The various kinds of deformations of the specimen under various temperature and moisture content, as well as the rheological behaviour of the specimen with water vapour passing through them were investigated. The testing condition is so designed for the better understanding of the theological behaviour of wood material in compression as it occurs in pressing process of particleboard. The viscoelasticity reveals the mechanical properties of high polymers of three dimensional network. The elastical compliance and retarded elastic compliance of the specimen increase only slightly with increasing temperature in the testing range (20—105℃) in ovendry condition, increase sharply with increasing temperature in wet condition or with water vapour passing through specimen. In the condition of room temperature, the elastic compliance and retarded elastic compliance increase definitely with increasing moisture content of specimen.