Use of Aluminum Coils Instead of Copper Coils in Accelerator Magnet Systems

Use of aluminum windings for the ac injector-synchrotron and dc storage ring magnet systems has been studied. 1, 2 The injector synchrotron is an 18-Hz fast-cycling 8-GeV accelerator that feeds protons to the 200-GeV main ring. The physical properties of aluminum are discussed, as are the extrusion of the conductor and the winding of the coils. Also included is a discussion of cooling-system problems and their solution. Important design conditions for aluminum coils are given. An economic analysis of aluminum- and copper-coiled magnet systems is presented. As an example, the injector-synchrotron magnet system is compared to a dc storage-ring magnet system with the same magnetic characteristics. The optimum coil current density is discussed, as are the effect of gap field, economic life, and core shape on cost and optimum current density. Physical and economic advantages of aluminum coils for magnet systems are presented as are conditions under which the use of aluminum coils should be avoided.