Mechanisms of the formation of a bulk superconducting phase MgB2 at high temperatures

Abstract

The structure of MgB 2 samples synthesized from magnesium flakes and a boron powder at tem peratures of 900-1000°C has been investigated. It has been found that the samples have "dendrite like" and layered structures formed as a result of the dissolution of solid boron in liquid magnesium followed by crys tallization. The obtained structures have been analyzed within the theoretical concepts of crystallization from melt.