Abstract: Desorption processing of poplar(Populus euramericana Cv.)with size of 20 mm× 20 mm×10 mm were investigated from 100% to 3 different relative humidity conditions of 22%, 47%, and 75% at 25℃. A self-designed temperature chamber was used in order to take thermal images at a certain time intervals during the processes. The results showed that with the moisture content of the specimens decreased, the average temperature were also reduced of 1-5 ℃ at the beginning of desorption process. During the desorption process, the moisture content and average temperature of the specimens was gradually approaching the equilibrium state. The temperature for center layer along the longitudinal direction of the specimens was higher than that for surface layer. The temperature difference between the center and surface reached the maximum value of 0.7 ℃ at the first 5 min and eventually reduced to 0.2 ℃ at equilibrium state.

Key words: wood, desorption, moisture content, temperature, infrared thermal imaging