Methods, systems, and articles of manufacture for fastening internal cooling fans to claw-pole segments are provided. A claw-pole segment suitable for use in a rotor of an electromechanical machine is formed. The claw-pole segment may include a base portion, at least one claw pole projecting axially from the base in a first direction, and at least one protrusion projecting axially from the base in a second direction opposite the first direction. A fan assembly that attaches to the claw-pole segment is also formed. The fan assembly may include at least one opening for receiving the at least one protrusion, and may be formed with varying configurations to affect the frequency response of the fan. The portion of the at least one protrusion extends through and beyond the opening of the fan assembly when the fan assembly is mounted on the claw-pole segment and expands in response to an application of an axial load, to secure the fan assembly to the claw-pole segment.