Abstract: A rotating target ion bombard or implant apparatus with an arrangement for cooling the target. The cooling arrangement utilizes a pattern of air openings or passages and air fins. The pattern of air openings are positioned concentric to the disc hub and act to separate the hub region of the disc from the outer target or work region. The air openings function to both reduce the conductive cross-section between the hub region and outer work region of the disc and permit air to pass from the implant or bombard side to the back surface thereof. The air fins are provided on the back surface of the disc to draw air through the openings when rotating. Cooling is achieved by rotating in atmosphere during the load/unload cycle of operation. Reduction of the conductive cross-section between work region and hub region reduces heat transfer to the ferrofluidic feedthrough means coupled to the hub region thereby increasing the ferrofluidic feedthrough means lifetime.