High-Pressure Treatment of Chinese Fir Wood: Effect on Density, Mechanical Properties, Humidity-Related Moisture Migration, and Dimensional Stability
A new densification technique for industrial uses of plantation wood was studied. Chinese fir wood was treated by high pressure (HP) at 50 to 200 MPa for 5 min. The density and mechanical properties, moisture sorption isotherm (MSI), and dimensional changes of the pressure-treated wood under various...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
North Carolina State University
2016-10-01
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| Series: | BioResources |
| Subjects: | |
| Online Access: | http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_4_10497_Li_High_Pressure_Treatment_Chinese_Fir |
| Summary: | A new densification technique for industrial uses of plantation wood was studied. Chinese fir wood was treated by high pressure (HP) at 50 to 200 MPa for 5 min. The density and mechanical properties, moisture sorption isotherm (MSI), and dimensional changes of the pressure-treated wood under various relative humidity (RH) storage conditions were evaluated. The densities of HP-treated wood ranged from 0.79 ± 0.01 g/cm3 after treatment at 50 MPa to 0.92 ± 0.02 g/cm3 at 200 MPa, which was significantly higher (p < 0.05) than that of the control (0.35 ± 0.01 g/cm3). Hardness values in radial and tangential fiber alignment faces also significantly increased by 370% to 470% and 350% to 460%, respectively, as compared with the control. The modulus of elasticity and the modulus of rupture of pressure-treated wood increased by 48% to 88% and 89% to 170%, respectively. The equilibrium moisture content varied with RH, decreasing slightly at 33% and 52% while significantly increasing (p < 0.001) at 86% and 93% RH. Radial, tangential, and volumetric dimensions of densified wood were relatively stable at 33%, 52%, and 67% RH, while remarkable swelling occurred at 86% and 93% RH. |
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| ISSN: | 1930-2126 1930-2126 |