Abstract: A conductor bar of a cage rotor of an asynchronous machine has a longitudinal extension and includes first and second sections in the longitudinal extension. The first section has a hardness which is lower than a hardness of the second section and is realized through soft annealing, brief inductive heating or heating by a flame so as to enable a compression of the first section of the conductor bar by way of axial pressure after axially joining the conductor bar in a slot of a magnetically conductive body of the cage rotor, with the first section abutting an inner wall of the slot of magnetically conductive body of the cage rotor.