The Effect of Thermal Treatment on Color and Dimensional Stability of Eucalyptus

In this study, the effect of thermal treatment on color, moisture absorption performance, and dimensional stability of Eucalyptus (Eucalyptus grandisxE. urophylla) was investigated. Wood specimens were subjected to different thermal treatment conditions at 160, 180, 200, and 220 degrees C for 1, 2, 3, and 4 hour(s). The results show that thermal treatment brought a darkened color in the thickness direction, decreased moisture absorption performance and increased dimensional stability. Compared with the untreated wood, lightness index L*, green-red index a*, blue-yellow index b*, equilibrium moisture content (EMC), water absorption (WA), and volume swelling (VS) for treated wood could be decreased up to 53.78%, 47.87%, 80.05%, 52.18%, 58.34%, and 75.95%, respectively. The higher the treatment temperature and the longer the treatment time, the lower the color index, equilibrium moisture content, water absorption and volume swelling, and the temperature has a greater influence than time on dimensional stability of samples.