Influence of eutectic microstructure on the critical current density of V1−xZrx superconductors

We present here the studies on the effect of annealing on the structural and magnetic properties of V1−xZrx (x = 0.33 and 0.40) superconducting alloys. We show that the γ-ZrV2 phase grows at the expense of (α-Zr)-(γ-ZrV2) eutectic microstructure when V1−xZrx alloys are annealed at 1473 K for one week. The annealed samples predominantly have a γ-ZrV2 phase with small amounts of β-V and α-Zr phases. The irreversibility field, critical current density, and pinning force density of the as-cast samples are found to be significantly higher than those of annealed alloys. These results indicate that eutectic microstructure is important in utilizing these materials for high field applications.