MgB2 superconducting wire fabricated by using Mg4Ag as starting materials

MgB2 with <f>Tc</f> of 37 K could be fabricated through the diffusion reaction between Mg4Ag and amorphous B at relatively low temperatures above 550 °C. The melting point of Mg4Ag is 472 °C, much lower than that of pure Mg (650 °C). Therefore the reaction between Mg4Ag and B is a liquid–solid diffusion reaction. We also tried to fabricate MgB2 wires through a powder-in-tube method and an in situ reaction process by using Mg4Ag powder and amorphous B powder as the starting materials. The <f>Jc–B</f> properties of the wires depend on not only the size of starting powder but also the reaction temperature. [Copyright &y& Elsevier]