About Conductors

During the operation of high field magnets, mechanical forces are exerted on the magnet itself, and electrical energy is converted into heat. Excesses in one or both of these forces, beyond the material and magnet design limits can lead to magnet failure. In order to withstand the stresses, and to minimize heating, materials are needed that combine both high mechanical strength and high electrical conductivity. Due to their nature, mechanical strength and electrical conductivity oppose each other. In other words, whatever one does to increase the strength will inevitably decrease the conductivity. Our goal is to find the most effective strengthening mechanisms that reveal a minimal loss in conductivity for each type of conductor. Furthermore, we want to develop and describe a processing route for these newly developed and/or optimized conductors that can then be applied in industry to supply us and other markets with better high strength conductors.

The specific demands for high strength conductors, when applied in high field magnet technology, strongly depend on the individual magnet design. Bitter magnets are continuously cooled during operation, their design is such that the materials are mechanically stressed to between 90 and 95 percent of their yield strength. Pulsed magnets are pre-cooled in liquid nitrogen and reach room temperature shortly after the pulse. Their yield strength may be exceeded during the pulse, and reinforcement as well as ductility of the conductor are needed for "survival" of the pulse.

Several approaches have been made in order to achieve a good combination of mechanical strength and electrical conductivity. This table lists the current commercially available high strength conductors used at the Mag Lab, as well as some of their specifications.

For more information, please contact Dr. Ke Han at han@magnet.fsu.edu or (850) 644-6746.