2004/09/15 by Shi Xue Dou, S. X. Dou, S. Soltanian +8 · 1 citation
Chemistry · Materials Science · Physics and Astronomy · #Analytical Chemistry (journal) #Chemistry #Condensed matter physics #Crystallography #Diffraction #Doping #Iron-based superconductors research #Lattice constant #Materials science #Nanoscopic scale #Nanotechnology #Optics #Optoelectronics #Physics of Superconductivity and Magnetism #Superconductivity #Superconductivity in MgB2 and Alloys #Transmission electron microscopy #cond-mat.supr-con
paper · pdf · doi:10.1088/0953-2048/18/5/022
arxiv created 2004/09/15 · openalex publication_date 2005/04/05 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Iron is an important sheath material for fabrication of MgB 2 wires. However, the effect of Fe doping on the superconducting properties of MgB 2 remains controversial. In this work, we present results on nanoscale Fe particle doping in MgB 2 . The Fe doping experiments were performed using both bulk and thin film forms. Neither free Fe particles nor FeB compound was detected at 1% Fe doping by means of either transmission electron microscopy (TEM) or x-ray diffraction (XRD), suggesting that Fe substituted for Mg in the lattice. The level of Fe substitution for Mg is estimated to occur at a level lower than 1% of Mg, and this substitution is proposed to be responsible for the decrease in transition temperature with Fe doping. Because of the high reactivity of nanoscale Fe particles, Fe doping is largely in the form of FeB at a Fe doping level of 2% while Fe 2 B was detected at 10% Fe doping by means of both XRD and TEM. The J c ( H ) performance was severely depressed at above a 2% doping level. The detrimental effect of nanoscale Fe doping on J c ( H ) is attributable to both the Fe substitution for B in the lattice structure and the inclusions of Fe and FeB which act as weak links at grain boundaries.