MECHANICAL PROPERTIES OF MgB2 HOLLOW WIRES

The peculiar morphology of the MgB2 wires resulting from the reactive liquid Mg infiltration technology (Mg-RLI), characterized by an annular distribution of the superconducting material, originates a peculiar mechanical behaviour Monofilament wires of different size and different thickness of the superconducting material have been subjected to tensile and flexural deformation, in order to gain a comprehensive description of the mechanical behaviour of the superconducting material. A model based on a simplified description of the mechanical behaviour in term of few parameters aids the interpretation of the vanous experimental measurements and represents a tool to evaluate the mechanical behaviour of different specifically sized wires. Other variables entering in the mechanical model take into account the filling of the internal hole with the metallic Mg and the strength of the external metallic sheath. The present mechanical analysis gives hints on the limits of applicability of the react-and-wind process in magnet manufacturing with this kind of wires. A further output of the study is to find the variation of the intrinsic mechanical properties of the MgB2 material as a function of the Carbon doping, obtained via SiC doping.