林业科学2018，Vol.54Issue(4)：76-83,8.DOI:10.11707/j.1001-7488.20180409
不同纹理方向栎木微小无疵试样板材蠕变特性
Orthotropic Creep Performance of Small Flawless Oak Board
摘要
Abstract
[Objective] In order to clarify the softening and flattening mechanisms of oaks in different cutting directions,bending creep behavior of different oak boards (longitudinal plain-sawed lumber,longitudinal quarter-sawed lumber,transverse plain-sawed lumber and transverse quarter-sawed lumber) were investigated by dynamic mechanical analysis(DMA).[Method] DMA creep curves of oak samples were analyzed and fitting by Burger model and general Kelvin model to evaluate the creep performance of different oak samples.[Result] The results showed that both Burger model and general Kelvin model could describe creep characteristic of oak well,R2 of Burger model is larger than 0.90 and R2 of general Kelvin model is larger than 0.99.Under the same moisture content,the elastic module(E0)and bulk viscosity(ηn),which were calculated by general Kelvin model,decreased with temperature increasing from 70 to 90 ℃.The retarded time(T'),which were calculated by Burger model,increased when the temperature increased from 70 to 90 ℃.According to ηn,it was the following order:longitudinal plain-sawed lumber ＞ longitudinal quarter-sawed lumber ＞ transverse quarter-sawed lumber ＞ transverse plain-sawed lumber.[Conclusion] It was suggested that the higher the temperature,the much easier for the oak board flattening.Transverse warp of oak board was easier to flat than that of longitudinal warp.Longitudinal warp of plain-sawed lumber was harder to flat than quarter-sawed lumber.However,comparing to quarter-sawed lumber,restoration of transverse warp for plain-sawed lumber was easier.关键词
栎木/各向异性/Burger模型/黏弹性Key words
oak/orthotropic/Burger model/viscoelasticity分类
农业科技引用本文复制引用
王聪,吴强,林鹏,杨东,俞友明..不同纹理方向栎木微小无疵试样板材蠕变特性[J].林业科学,2018,54(4):76-83,8.基金项目
浙江省自然科学基金项目(LY16C160010) （LY16C160010）
浙江省家具检测技术研究中心重点实验室基金(2016J03). （2016J03）
