Energy dissipation in the non-propagating surface cracks in steel round bar at torsional vibration

In a result of experimental investigations of steel R2M cylindrical specimens with a surface transverse and slant crack at torsional vibrations it was revealed that the damping characteristic of the specimens is strongly dependent on the crack sizes and stress amplitude. The energy dissipation in the non-propagating transverse crack is caused mainly by the plastic area along the crack front and practically is not related to the friction between the crack faces. The level of energy dissipation in this crack is determined uniquely by the equivalent stress intensity factor.