Effect of heat treatment on mechanical properties of hazelnut wood (Corylus colurna L.)

Heat treatment is widely used to improve the dimensional stability of wood and wood products. The objective of this study was to evaluate effects of heat treatment on mechanical properties of hazelnut wood (Corylus colurna L.). Samples were exposed to temperature levels of 120 °C, 150 °C, and 180 °C for time spans ranging from 2 to 10 h Mechanical properties including compression strength, modulus of elasticity, modulus of rupture, Janka-hardness, impact bending strength, tension strength perpendicular to grain, tension strength parallel to grain, shear strength, and cleavage strength of heat-treated samples were determined. Maximum reduction values of 68.11%, 64.97%, and 58.75% were found for Janka-hardness in radial, tangential, and tension strength parallel to grain for the samples exposed to 180 °C for 10 h, respectively. Overall results showed that treated samples had lower mechanical properties than those of the control samples. Statistically significant difference was determined (p = 0.05) between mechanical properties of the control samples and those of treated at 180 °C for 10 h.