Title :
R&D studies on mechanical stress of 1 GHz NMR magnet
Author :
Ozaki, O. ; Kosuge, M. ; Kiyoshi, T. ; Yuyama, M. ; Wada, H. ; Kamikado, T. ; Murakami, Y. ; Miyazaki, T. ; Hayashi, S. ; Kawate, Y.
Author_Institution :
Nat. Res. Inst. for Metals, Ibaraki, Japan
fDate :
6/1/1999 12:00:00 AM
Abstract :
In order to make a 1 GHz NMR magnet compact, it is operated under high hoop-stress conditions. In our design the hoop-stress of a 1 GHz NMR magnet exceeds 180 MPa. We prepared two types of sample coils. One of them was constructed with niobium-tin superconducting wire, which has a tantalum core. The other one was wound with niobium-titanium superconducting wire. These wires are rectangular in cross-section. The niobium-tin sample coil was energized in a backup magnetic field of 13.5 T and 14 T. It was possible to operate it up to a hoop-stress of 272 MPa. The niobium-titanium sample coil was tested up to 99% of its critical current where the hoop-stress was 226 MPa. These results confirm that our design of the 1 GHz NMR magnet is appropriate.
Keywords :
critical current density (superconductivity); niobium alloys; nuclear magnetic resonance; stress analysis; superconducting coils; superconducting magnets; tin alloys; titanium alloys; 1 GHz; 13.5 T; 14 T; 226 MPa; 272 MPa; NMR magnet; Nb/sub 3/Sn; NbTi; backup magnetic field; critical current; high hoop-stress conditions; mechanical stress; niobium-tin superconducting wire; niobium-titanium sample coil; niobium-titanium superconducting wire; rectangular cross-section; tantalum core; Magnetic cores; Niobium compounds; Niobium-tin; Nuclear magnetic resonance; Stress; Superconducting coils; Superconducting filaments and wires; Superconducting magnets; Titanium compounds; Wounds;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
