A torsional-vibration damper includes at least one primary element and a secondary element that can be coupled to each other by a spring device, are limited in movement in relation to each other about a rotational axis, and can be brought into frictional contact with each other by a friction device. The friction device has at least two friction-surface-carrying elements rubbing against each other to which a contact-pressure force, generated by a force-generating device, can be applied to produce a frictional engagement between the two elements. The force-generating device has a mechanical actuating mechanism for generating an actuating force and a hydraulic actuating mechanism for generating a counterforce, wherein the contact-pressure force is a vector sum of the actuating force and the counterforce.