Computer modeling of magnetic flux pinning by grain boundaries in high-field superconductors

We report here some results for the critical current density of a high-field superconductor such as Nb3Sn calculated with a simple two-dimensional model using computer simulation methods similar to those of Brandt[1] and utilizing an expression for the magnetic flux line-grain boundary interaction energy derived by Welch[2] based on the electron-scattering mechanism.