Influence of combined hygro-thermo-mechanical treatment on technical characteristics of poplar wood

Maderas: ciencia y tecnologia

Navi, Parviz¹  Hajihassani, Reza²  Najafi, Saeed Kazemi²  Mohebby, Behbood² 

[1] Bern University of Applied Sciences, Bern, Switzerland;Tarbiat Modares University, Noor, Iran

关键词: Compression set;    hygrothermal treatment;    mechanical properties;    physical properties;    Populus deltoides;    wood densification.;   

DOI  :  10.4067/S0718-221X2018005011001

学科分类：农业科学（综合）

来源: Universidad del Bio-Bio

【 摘 要 】

Combined hygro-thermo-mechanical technique was adopted and used for densification of poplar wood instead of sole treatment. This technique is combination of two techniques of hygrothermal treatment and densification of wood. For treatment, poplar wood blocks were initially treated hygrothermally at temperatures of 130, 150 and 170°C for holding time of 20, 40 minutes. Afterwards, the densification process was carried out under a hot press (temperature 160°C for 20 minutes). For densification compression set was adjusted for 40 and 60 % based on the initial thickness (radial direction) of the blocks. The densified and non-densified wood blocks were tested for physical and mechanical properties as density, water absorption, thickness swelling, springback, bending strength, modulus of elasticity as well as shear strength parallel to grain. Results revealed that wood properties were enhanced due to the combined hygro-thermo-mechanical -treatment. According to the results, wood density was increased due to the combined hygro-thermo-mechanical -treatment significantly. The treatment improved the dimensional stability of the densified samples. It was also found that the combined hygro-thermo-mechanical -treatment could significantly improve mechanical properties and also reduce the springback in the densified poplar wood.

【 授权许可】

CC BY-NC