React-Wind-Sinter Technology for Bi2Sr2CaCu2Ox

The superconductor Bi2Sr2CaCu2Ox (Bi2212) is currently being considered for high field particle accelerator magnets. Bi2212 has the highest Jc of any practical superconductor at fields greater than 15 Tesla. Thus it will be needed for making high field magnets to improve the performance of machines such as the Large Hadron Collider and Muon Collider. However, the processing requirements for Bi2212 are extremely stringent. It is very difficult to produce a reliable magnet of the size needed for these applications. Making accelerator magnets using Bi2212 represents a difficult and high risk technology. Since these high field accelerator magnetics are very expensive, the loss of a magnet has a significant financial impact on the program. Therefore, this project will develop an alternate fabrication process involving react-wind-sinter (RWS) technology. RWS breaks the heat treatment cycle into two independent segments. Process control is not nearly as stringent for RWS as it is for the conventional approach and is well within commercial capabilities. Thus large magnets can be fabricated without the concern for temperature variations and gradients in the magnet windings that lead to poor properties and magnet performance. The Phase I project demonstrated the viability of the process. The Phase II project will develop a commercially practical magnet fabrication technology for Bi2212 magnets based on the RWS process.