Electromechanical Behavior of ${\hbox{Bi}}_{2}{\hbox{Sr}}_{2}{\hbox{CaCu}}_{2}{\hbox{O}}_{\rm x}$ Conductor Using a Split Melt Process for React-Wind-Sinter Magnet Fabrication

A new approach to magnet fabrication, react, wind and sinter (RWS), has been proposed for Bi2Sr2CaCu2Ox (Bi2212), magnets. In this process, the conventional Bi2212 heat treatment is split into two portions, and the magnet is wound between these heat treatments. Here we report results on the RWS "split melt process". Significant increases in Ic are obtained in Bi2212 round wires compared to standard melt processing. Strain effect measurements, using the Lorentz force, indicate that RWS wires have similar mechanical performance as wind and react wires. Effects of the split melt temperature on the electromechanical properties are also reported. These results show that split melt processing and RWS magnet fabrication are viable approaches for Bi2212 conductors and magnets.

[1]  J. Schwartz,et al.  Proof-of-principle experiments for react–wind–sinter manufacturing of Bi2Sr2CaCu2Ox magnets , 2007 .

[2]  P. Noonan,et al.  High Field Insert Coils From Bi-2212/Ag Round Wires , 2007, IEEE Transactions on Applied Superconductivity.

[3]  M. Rudziak,et al.  Reactions Between Bi-2212 and Silver-Nickel Composite Sheath , 2007, IEEE Transactions on Applied Superconductivity.

[4]  J. Schwartz,et al.  Statistical analysis of the electromechanical behavior of AgMg sheathed Bi2Sr2CaCu2O8+x superconducting tapes using Weibull distributions , 2007 .

[5]  J. Schwartz,et al.  Perspective on a Superconducting 30 T/1.3 GHz NMR Spectrometer Magnet , 2006, IEEE Transactions on Applied Superconductivity.

[6]  Ulf P. Trociewitz,et al.  The generation of 25.05 T using a 5.11 T Bi2Sr2CaCu2Ox superconducting insert magnet , 2004 .

[7]  J. Schwartz,et al.  Effect of processing defects on stress-strain-I/sub c/ for AgMg sheathed Bi-2212 tapes , 2003 .

[8]  David C. Larbalestier,et al.  Advances in superconducting strands for accelerator magnet application , 2003, Proceedings of the 2003 Particle Accelerator Conference.

[9]  M. Sumption,et al.  Bi:2212/Ag-based Rutherford cables: production, processing and properties , 1999 .

[10]  J. Schwartz,et al.  Mechanical Properties and Strain Effects in Bi2Sr2CaCu2Ox/Ag Composite Conductors , 1998 .

[11]  H. Garmestani,et al.  Mechanical properties and strain effects in Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub x//AgMg composite conductors , 1997, IEEE Transactions on Applied Superconductivity.

[12]  Arno Godeke,et al.  Descriptive model for the critical current as a function of axial strain in Bi-2212/Ag wires , 1996 .

[13]  B. Ten Haken,et al.  Compressive and tensile axial strain reduced critical currents in Bi-2212 conductors , 1995, IEEE Transactions on Applied Superconductivity.

[14]  J. Tenbrink,et al.  High‐field critical current densities in Bi2Sr2Ca1Cu2O8+x/Ag wires , 1989 .