<Original>Permanent Fixation of Bending Deformation in Wood by Heat Treatment

Abstract

This article deals with the effect of heat on the fixation of bending set in wood. The wet specimen irradiated with microwave was bent around a form by using a metal strap. The bent specimen was oven-dried under restraint to fix its deformation, then heat-treated. The recovery tests by wetting, ovendrying and boiling for the bent specimens were conducted. With increasing heating temperature and time, the recovery of bending set diminished. There was an excellent linear relationship between the recovery of radius of curvature and the recovery of strain in the concave face. Almost complete fixation of set was achieved by the heat treatment above 30 hr. at 160℃ and at around 12 hr. at 180℃.