Description:
<jats:title>Abstract</jats:title><jats:p>Flux pinning by grain boundaries in anisotropic superconducting materials is studied by assuming that pinning comes through the local change in the Ginzburg‐Landau free energy. The experimental results of Kes and others on the Nb sample, containing grain boundaries as lattice defects, are explained by Labusch's theory. The results are discussed.</jats:p>