Surface-hardened, rotationally symmetrical workpiece, hardening method and hardening apparatus

A method, comprising:

• obtaining a rotationally symmetrical workpiece with a lateral surface and a longitudinal axis, wherein at least a portion of the lateral surface comprises hardened portions of differing diameters formed by:
• generating, via at least one laser device, concentrated high-energy laser radiation that acts on an area of action of the lateral surface;
• moving the at least one laser device along the longitudinal axis of the workpiece such that the laser radiation acts on differing portions of the lateral surface along the longitudinal axis of the workpiece;
• rotating the workpiece about its longitudinal axis at a first rotational speed when the laser radiation acts on a first portion of the lateral surface along the longitudinal axis having a first local diameter to form a first hardened portion;
• and
• rotating the workpiece about its longitudinal axis at a second rotational speed that differs from the first rotational speed when the laser radiation acts on a second portion of the lateral surface along the longitudinal axis having a second local diameter that differs from the first local diameter to form a second hardened portion,
• wherein the first and second rotational speeds of the workpiece are dependent on the radiation output of the laser device, the size of the area of action and the respective first and second local diameters of the workpiece, such that an energy per unit area that is introduced into the first and second portions is substantially constant.