Filament and interface structure of in-situ MgB_2 wires

摘要

The structure of MgB_2 filaments and interface areas of in-situ made composite MgB_2/Ti/Cu/Monel wires sintered at temperatures 650-850°C were studied by polarized light optical microscopy and Vickers microhardness. The microhardness can be used for the filament density evolution and also for the sensitive detection of sheath contamination. The temperature dependent MgB_2/Ti and Ti/Cu interface reactions were studied. The presented results give useful information above how the applied composition and annealing can affect the core density, J_c and interface diffusion/reaction.