Effects of Heat Treatment on Physical-Mechanical Properties of Eucalyptus regnans

Eucalyptus regnans was subjected to thermal treatment. The samples were placed in superheated vapors at 120, 130, 140, 150, 160, 170, 180, 190, and 200 °C at ambient pressure to determine the effect of heat treatment on the physical-mechanical properties of Eucalyptus regnans. The results showed that heat treatment played an important role in the impact toughness, nail-holding ability, surface hardness, bending strength, and bending modulus of elasticity of E. regnans. The nailholding ability, surface hardness, bending strength, and bending modulus of elasticity of E. regnans treated at 120 and 130 °C increased related to untreated wood, but decreased at 140 to 200 °C. The impact toughness decreased after heat treatment from 120 to 200 °C, while the bending modulus of elasticity increased. Consequently, heating at 120 and 130 °C was found to be more suitable to ensure sufficient strength.