Stability considerations of multifilamentary MgB2tape

The risk of overheating arises if the stability of an MgB 2 coil is lost. This is mainly due to the low thermal conductivity of the matrix metal, which is typically iron or nickel. Due to a strong chemical reaction, copper can be used in contact with MgB 2 only in specific cases: in situ preparation route and low formation temperature. However, recent developments in the manufacture of MgB 2 conductors have resulted in stabilized MgB 2 tapes. In any case, the stability considerations of MgB 2 conductors are of great importance. We studied computationally the stability of an MgB 2 /Ni/Fe/Cu tape manufactured by Columbus Superconductors. First, the effective material properties of the tape were computed. Based on these material properties, we computed the basic quench characteristics (minimum propagation zone, minimum quench energy and normal zone propagation velocities) for the tape at 15, 20 and 25 K. The tape unit cell model was used in computations. The computed stability results were compared with the measured ones of a monofilament MgB 2 /Cu/Ni tape and commercial LTS and HTS. According to the results, the basic quench characteristics computed fit between the ones of LTS and HTS materials.