Compression of Wood with Superimposed Small Sinusoidal Oscillations. Part II: High Temperature
Keywords:Compression, sinusoidal oscillations, fiber damage
The changes occurring in wood when it is subjected to compression straining 7.0% parallel to the grain or 10.0% perpendicular to the grain in the temperature range 70-170 C have been studied. Small dynamic strain oscillations at a frequency of 9 Hz were superimposed during the straining.
The changes occurring in the wood have been determined by measurement of the resulting permanent strain of the wood specimens. Fiber damage has been evaluated by measuring the intrinsic viscosity of the pulp after a standardized sulfite delignification. Some microscopic examinations were also carried out. The energy consumption during compression treatment has also been considered.
Compression straining at temperatures of 150 C and above was found to be favorable with respect to wood disintegration yielding a high degree of wood deformation with low fiber damage and at low energy consumption.
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