| 摘要 |
A method is described for the preparation of superconductor massive bodies o f MgB2, having a density close to the theorical value, which comprises the following passages: mechanical activation of crystalline boron with the formation of activated powders; formation of a porous preform of said powder s; assembly of the porous boron preform and massive precursors of metallic magnesium in a container and sealing thereof in an atmosphere of inert gas o r with a low oxygen content; thermal treatment of the boron and magnesium as assembled above, at a temperature higher than 700 ~C for a time greater than 30 minutes, with the consequent percolation of the magnesium, in liquid phas e, through the activated crystalline boron powders.
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