E. I. Kuznetsova, M. V. Degtyarev, T. P. Krinitsina, Yu. V. Blinova

THE STRUCTURE OF MgB₂ CERAMICS SYNTHESIZED UNDER QUASI-HYDROSTATIC PRESSING

The paper deals with the issues of compaction and the formation of the structure of the MgB₂ compound obtained under the conditions of all-around compression in a Toroid chamber (quasi-hydrostatic pressing), due to which the product has almost the same density throughout the volume. It is shown that the densest finely dispersed ceramics with a grain size of ~100 nm can be obtained from the synthesized MgB₂ compound by quasi-hydrostatic pressing (P = 4–5 GPa) at room temperature followed by reductive annealing. Deformation and annealing combined made it possible to obtain ceramics with a density of 2.4 g/cm³ and a critical current density of 6.7×104 A/cm² (at 30 K).

Acknowledgment: The research was performed on the equipment of the Testing Center of Nanotechnology and Advanced Materials collective use center of IPM UB RAS. We are grateful to A. V. Pasheev for deforming the samples. The work was performed within the state assignment on the subject of Pressure (No. AAAA-A18-118020190104-3) and supported by UB RAS project No. 18-10-2-24.

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