摘要
在不同温度和平衡含水率条件下研究南方阔叶树材干燥初期应变特点。试验结果表明，干燥初期表层呈现伸张弹性应变和塑性应变，内层为压缩应变，伸张弹性应变的最大值是产生表裂的主要原因，塑性应变而引起的表层固定变形是产生内裂的原因。弹性和塑性应变受平衡含水率的影响较大，并且与含水率梯度存在相关关系、干燥初期阶段的延续时间，可由表层达到最大伸张应变时的含水率与初含水率的比值来确定。
Features of the strains in some southern hardwoods during the first drying stagewere studied under various temperature and equilibrium moisture content.The results shownthat surface layer represented tensile elastic strain and plastic strain , while internal layerrepresented compress strain. The maximum tensile elastic strain was the main factor whichresulted in surface-checking,and the set caused by plastic strain was the reason of inner-checking.The elastic and plastic strain were greatly influenced by the equilibrium moisturecontent and interrelated with the MC gradient.Drying time during the first drying stage bedetermined by the ratio of the MC when the surface reached the maximum tensile strain andthe initial MC.
出处
《木材工业》
北大核心
1995年第4期6-11,共6页
China Wood Industry
基金
林业部资助项目
