Conveners
Sat-Af-Or4 - Advances in Nb3Sn and MgB2 Conductors II
- Ariel Haziot (CERN)
- Guram Chlachidze (FNAL)
We introduced internal oxidation in Rod-in-Tube (RIT) Nb3Sn subelements, used in simplified restacked wire, by using SnO2 powders as an oxygen source (OS). During Nb3Sn synthesis, the OS decomposed, resulting in a grain size below 60 nm. This grain refinement is consistent with an increase of the critical current density (Jc) towards the performance...
The National Institute for Materials Science (NIMS) is ongoing the R&D on ultrafine Nb3Sn superconducting wires less than 50 microns in diameter. So far, we have successfully fabricated a kilometer-scale of Nb3Sn ultrafine wire through the bronze process. The starting billet was assembled by 19 Nb rods, a bronze alloy matrix of Cu-14%Sn-0.3%Ti. The outer diameter of the starting billet is...
Novel ultrafine jelly roll Nb3Sn ultrafine wires, i.e. ~50 μm diameter, offer the potential of building Nb3Sn magnets using the react-and-wind approach with high-Jc wires. The high flexibility of these wires due to their small diameter, the ability to assemble multiple of them in Rutherford cables, and the long unit lengths that have recently been manufactured motivates further studying the...
Superconducting magnets in particle accelerators currently use mostly a Nb-Ti alloy, which has a critical temperature (𝑇𝑐) of 9.2 K and a critical field (𝐵𝑐2) of 14.5 T. However, future particle accelerators, such as those beyond the LHC, will require dipole magnets capable of generating fields of 16 T or higher. This necessitates a shift to high-performance superconductors, with the...
Proposed 14 T Nb3Sn magnet designs for a future energy-frontier circular collider often call for wires with higher Jc, larger diameter and lower copper to non-copper (Cu:nonCu) ratio. As well as pushing Nb3Sn superconducting wire technology to its performance limits, these characteristics all prove challenging for magneto-thermal stability.
This study investigates the stability of Nb3Sn wires...
To develop superconducting wires suitable for applications demanding extremely high magnetic fields, we conducted an experimental investigation on the optimization of microstructure and heat treatment processes aimed at enhancing the critical current density (non-Cu Jc) at 16 T in Internal-tin type multifilamentary Nb3Sn superconducting wires fabricated in WST. Utilizing comprehensive...
MgB2 is one of the practical superconductors that has been widely studied over the past two decades. The internal magnesium diffusion (IMD) method serves as a promising method because it can enhance the grain connectivity of MgB2 phase and thereby improve the superconducting current of MgB2 wires. In this work, we successfuly fabricate the km-class 30-filament MgB2 wires using the IMD method,...
Commercially available Nb₃Sn wires with high critical current density are commonly used to manufacture high-field magnets (greater than 10T). To improve their current-carrying capacity, various types of Nb₃Sn wires have been developed. However, as the critical current increases, drawing the Nb₃Sn wire becomes more difficult, leading to larger filament sizes (on the order of hundreds of...
