MgB₂ is a material known for several years, but only recently discovered as superconductive at about 40 K. MgB₂ has a simple crystal structure with alternation of boron and magnesium layers, both in hexagonal array. It has mechanical strength and durability higher than superconducting oxides, weak-link-free grain boundaries, high transport critical current density (Jc),coherence length (>5 nm)higher than superconducting cuprates, low-cost starting materials and, above all, a transition temperature accessible to single stage cryocooler. Thanks to these properties, many efforts were done in order to synthesize MgB₂ for large-scale applications, in form of bulk, wires, tapes and films.
In this contribution, we present the results on the preparation and the characterization of MgB₂ thick films supported on Ti/Al₂O₃ and MoBN substrates via electrophoretic deposition technique (EPD).
We prepared superconducting MgB₂ thick films by following two different routes: i) deposition of MgB₂ powder, both pure and SiC doped, followed by a sintering step at high temperature and high Ar pressure in a furnace; ii) deposition of boron films and successive annealing in saturated Mg atmosphere at high Ar pressure.
The EPD deposition occurs at the anode of the electrochemical cell under an electric field of about 180 V/cm. The obtained films are homogeneous and well adhesive to the substrate. The MgB₂ films were then sintered at 1200 K in inert atmosphere, whereas the boron precursors were reacted with Mg at temperature over 1500 K and at high pressure of 1 GPa. X-ray diffraction confirmed the formation of a crystalline MgB₂ phase with hexagonal P6/mmm symmetry in the case of both MgB₂ and B precursors.
The electrical properties of the samples were measured in liquid helium vapour, by using an AC-bridge with the standard four-probes technique and indium contacts. The samples obtained from MgB₂ powder show high Tc of superconducting transition close to 35 K.

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