The objectives of this project were to determine thethermo-hygromechanical
densification process parameters necessary to produce high-density aspen veneers in a
steam injection hot press and determine their physical and mechanical properties.
Densification of aspen veneers from 3.2 mm to 1.6 mm thick was performed at 200, 220
and 240°C. The results show a very significant increase in density due to buckling of
fibers and vessel cell walls. Densified wood showed a reduced saturated moisture content
and equilibrium moisture content at 20°C and 50% relative humidity. Radial swelling
including compression set recovery after water soaking was 40% higher for densified
wood at 200°Ccompared to the control. It decreased for wood densified at 220 and
240°C.The moduli of elasticity and rupture in tension and bending and the Brinell
hardness were overall about twice as much as the control at 200°C and decreased at
higher temperatures. Treatment temperature had a very significant effect on wood color going. We are now focusing on treatment parameters resulting in an improved
dimensional stability.
temperatures higher than 200°C resulting in much darker wood. This project is still on