Abstract
Fatigue life of soft wood pulp fibers has been measured using torsion pendulum method. The fatigue life of wet pulp fibers decreases with an increase in torque and axial load. At the same stress level, the fatigue life of kraft fibers was greater than that of sulfite fibers. Drying and dry-wet cycles reduce the fatigue life of fibers.
The difference in the fatigue phenomena between never-dried fibers and the fibers subjected to drying or dry-wet cycles, and the difference between kraft and sulfite fibers are interpreted on the basis of irreversible changes in the cell wall structure and the formation of defects.
