Document Type : Research Paper

Authors

• Reza Hajihassani ¹
• Behbood Mohebi ²
• Saeid Kazemi Najafi ³
• Parviz Navi ⁴

¹ Ph.D Student, Department of Wood and Paper Sciences, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran

² Associate Prof., Department of Wood and Paper Sciences, Faculty of Natural Resources, Tarbiat Modares University, P.O. Box 46414-356, Noor, Iran

³ Prof., Department of Wood and Paper Sciences, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran

⁴ Prof., Department Of Architecture, Wood and Civil Engineering, Bern University of Applied Sciences, Bern, Switzerland

Abstract

Abstract
The present research work has investigated the physical and mechanical properties of hygro-thermally modified poplar (Populus deltoides) wood. The poplar wood blocks were treated hygrothermally at temperatures of 130, 150 and 170°C and for 20, 40 minutes as holding time. The physical and mechanical properties were determined for both treated and untreated wood. The properties; mass loss, collapse, specific gravity changes, dimensional stability, surface roughness, bending strength and modulus of elasticity, were determined prior to and after the treatment in all wood blocks. As expected, the hygrothermal treatment significantly improved the dimensional stability of the samples. It was also found that the hygrothermal treatment could increase collapse, surface roughness and modulus of elasticity due to the treatment. However, there were decreases in wood mass, specific gravity and bending strength of the treated poplar wood. It was revealed that the mass loss, decrease in the density as well as collapse in woos is correlated with treatment temperature as well as the holding time. While, raise of the treatment temperature as the holding time caused increase of the dimensional stability.

Keywords

• Hygro-Thermal Modification
• Holding Time
• Poplar (Populus deltoides)
• PHYSICAL AND MECHANICAL PROPERTIES

Main Subjects

• Biology and Wood Protection