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木材的纤维饱和点是什么?它是怎样影响木材的湿胀干缩的?

答案

参考答案:

当木材吸附水已达到饱和状态而又无自由水存在时,木材的含水率称为该木材的纤维饱和点。当含水量大于纤维饱和点时,表示木材的含水率除吸附水达到饱和外,还有一定数量的自由水,如受到干燥或受潮,只是自由水改变,不发生木材的变形;但含水率小于纤维饱和点时,表示水分都吸附在细胞壁的纤维上,它的改变会影响木材的变形。

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