尾巨桉木材的渗透性对皱缩的影响  

Effect of the permeability of Eucalyptus urophylla × E.grandis wood on collapse in drying

作　　者：苗平[1] 张耀丽[1] 庄寿增[1] 王晓敏[1] 陈佳荣[1] 范琤琤[1] 

机构地区：[1]南京林业大学木材工业学院,江苏南京210037

出　　处：《南京林业大学学报（自然科学版）》2010年第5期83-86,共4页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：国家自然科学基金项目(30771677)

摘　　要：对饱水状态下的尾巨桉木材气体渗透性进行了测量,并在不同干燥条件下进行了尾巨桉板材的干燥试验,观察其皱缩规律,探讨尾巨桉木材的渗透性对其干燥过程中皱缩的影响。结果表明:在尾巨桉木材的边心材交界处靠心材部位极易产生皱缩,尾巨桉木材边材的渗透性较大而心材的渗透性较小,当由边材向心材过渡过程中渗透性由大明显变小。当相对湿度一定时,温度越高皱缩深度越大;当温度一定时,相对湿度越低皱缩深度越大。心材部位渗透性差的主要原因是由于管孔内含有大量侵填体及导管间纹孔呈附物型的缘故。木材干燥过程的皱缩主要是由于木材内部产生的压应力,以及木材渗透性较小而产生较大的毛细管张力和水蒸气分压力差共同作用的结果。In this paper the gas permeability of wet Eucalyptus urophylla × E.grandis wood was measured,drying tests were carried in several drying conditions and the collapse rule was observed,then the effect of the permeability of E.urophylla × E.grandis wood on collapse in drying was discussed.The test results showed the region of the easy collapse in transition from sapwood to heartwood,and the sapwood permeability was larger than the heartwood and the permeability decreased quickly from sapwood to heartwood.When the relative humidity was constant,the higher the temperature was,the greater the depth of shrinkage was.When the temperature was constant,the lower the relative humidity was,the greater the depth of shrinkage was.The small permeability in heartwood mainly was due to there were large tylosis in the vessels and vestured pit between the vessels.The reason of collapse in the wood was actions result of the compressing stress generated interior during wood drying and the smaller permeability caused greater capillary tension and the vapor partial pressure difference.

关 键 词：尾巨桉 皱缩 渗透性 干燥 

分 类 号：S781.35[农业科学—木材科学与技术]