The results of the synthesis of nanocrystalline MgB2 superconducting compound by mechano-chemical reaction, followed by post-annealing were reported. The first stage of synthesis was carried out from elemental crystalline Mg and amorphous B powders by controlled mechanical alloying in a magneto-mill. X-ray diffraction studies revealed that the nucleation of small amount of MgB2 was initiated after 2-step milling for 100h under protective He gas. Further reaction to form MgB2 was accelerated by subsequent annealing of the milled powder at various temperatures. X-ray diffraction revealed the formation of well-developed nanocrystalline MgB2 after annealing of the pre-nucleated powder at 630–650C for a few hours.

Synthesis of Nanocrystalline Magnesium Diboride (MgB2) Metallic Superconductor by Mechano-Chemical Reaction and Post-Annealing. R.A.Varin, C.Chiu: Journal of Alloys and Compounds, 2006, 407[1-2], 268-73