Shrinking and Swelling Differences Between Hardwoods and Softwoods
Abstract
Using existing data in the Wood Handbook as a basis for calculations, it is shown that at similar specific gravities hardwoods shrink, and presumably swell, more than softwoods. A possible explanation to account for this difference in behavior is presented, in which the lower lignin content of hardwoods, resulting in a reduced restraint to dimensional change, is considered. Evidence is also presented indicating that at least for hardwoods, the relationship between specific gravity and volumetric shrinkage is not completely linear.References
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