The Effect of Proton Irradiation on the Critical Current of Commercially Produced YBCO Conductors

Abstract

Samples of YBCO superconductor from two manufacturers were irradiated with protons at the BLIP facility at BNL. Two specimens of each type of conductor were irradiated to five fluences covering the range from 10 16 to 4 10 17 protons cm 2 . The beam parameters for the irradiations were 42 A and 142 MeV. The critical current (zero field, 1 V cm) for all twenty samples was measured in liquid nitrogen before and after irradiation to quantify the effects of high-dose proton-induced radiation damage on the performance of the conductor, and thus evaluate its suitability for service in high-radiation environments. All of the specimens had a pre-irradiation current of about 100 A. This current decreased linearly with fluence, with a slope of about 20% per 10 17 protons cm 2 . The agreement between the two samples of each brand of conductor was exceptional.

Effect of proton irradiation on the critical current and critical temperature of Bi-2212 wires

“…Such magnets must be able to withstand the cumulative effect of the radiation over the life of a machine before the magnet performance degrades. In an earlier paper, the effects of proton irradiation on the critical current at 77 K of commercially produced YBCO tapes have been described [1]. In this paper we present the first measurements at 4.2 K of radiation damage effects on a Bi-2212 round wire that is obtained from industry.…”

Doubling the critical current density of high temperature superconducting coated conductors through proton irradiation

“…Typical p--beam currents of 200--300 nA were used. Proton irradiation has been used in numerous studies to enhance the vortex pinning in superconductors [6,7], although typically not in production--line CCs [8]. Earlier TEM work on YBCO single crystals showed that p--irradiation induces a mixture of defects consisting of point defects (mostly on the O and Cu sites), and clusters of point defects and small collision cascades, both anisotropic and 2 -5 nm in size [9].…”

Development of Radiation-Tolerant HTS Magnet for Muon Production Solenoid

“…The critical current measurements were then performed at a background field of 1 T for the irradiated samples. Although the behaviors of the two tapes varied significantly, neither showed any degradation or improvement of the critical current up to the irradiation level of 25 µA-h, indicating that the conductors can sustain the FRIB operation [21].…”

“…During the development of the FRIB magnet, an experimental program was launched to study radiation damage to the HTS tapes. Short samples of Yttrium-based ReBCO (i.e., YBCO) tapes obtained from SuperPower and ASC were irradiated with a 142-MeV proton beam at the Brookhaven Linear Isotope Production facility [18,21]. The critical current of the irradiated samples was first measured under a 77-K self-field condition, and the results demonstrated a monotonic degradation of the critical current [16].…”