ImprovedJ_cof MgB₂superconductor by ball milling using different media

Abstract

In this paper, the effects of ball milling B powders using different media, such as acetone, ethanol, and toluene on the superconducting properties of MgB 2 have been studied. It was observed that toluene medium was the most effective of them all for enhancing J c . J c was estimated to be 5 x 10 3 A/cm 2 at 8 T and 5 K. This value is much higher than that of pure MgB 2 that was not ball milled, by a factor of 20. It was considered that ball-milled B using toluene leads to smaller MgB 2 grains, resulting in enhanced J c at low operating temperature and high field.

Recycled-copper-filled epoxy composites: the effect of mixed particle size

“…During ball milling, powders were trapped between colliding balls and were subjected to high stress. Consequently, powders were subjected to a severe plastic deformation which exceeds their mechanical strength (Xu et al 2006). Thus, when the milling time or processing time was increased, the finer powders were obtained.…”

“…Indeed, in most cases, the rate of particle refinement (i.e. particle size and/or crystallite size) is roughly logarithmic with the processing time or ball-to-powder ratio (Xu et al 2006). Figure 1 shows the particle size distribution obtained through a Malvern particle size analyser (Malvern Instruments, Malvern, UK).…”

Properties Of MgB2/Ga Composites Prepared By Mechanical Alloying

“…First, sintered MgB 2 usually shows a poor densification with a large amount of intergranular pores which results in low critical current density [4,5]. So far, two methods have been commonly employed for the synthesis of MgB 2 : in-situ reaction of elemental Mg and B powders, and ex-situ method using pre-alloyed compound as a starting material.…”

Influence of Mg particle size on the reactivity and superconducting properties of in situ MgB2

“…For technological applications long conductors with high irreversibility field (H irr ), upper critical field (H C2 ) and infield critical current density (J C (H)) are required. For in situ synthesized MgB 2 , the H irr , H C2 and J C (H) depend sensitively on factors like flux pinning, microstructure, grain connectivity, density, chemical composition and homogeneity of the samples, which are influenced by the process conditions, as well as the purity, size, nature and stoichiometry of starting raw powders [2,[7][8][9][10][11][12][13][14][15][16].…”