当木材含水率达到纤维饱和点后,含水率再增加,仅增加木材中的自由水分,填充于木材的大毛细管中。在木材中,吸附和吸湿的水分分子与木质有强的物理—化学结合,不能单独同电场相互作用;而自由水与纯水的性质类似,其水分分子能单独同电场 When the moisture content of the wood reaches the saturation point of the fiber, the moisture content increases again, increasing only the free moisture in the wood and filling in the large capillary of the wood. In wood, the adsorbed and hygroscopic moisture molecules have a strong physico-chemical combination with the wood and can not interact with the electric field alone; whereas the free water behaves in a similar manner to pure water, and the water molecule alone can interact with the electric field