Study of NbB2 Addition on the Superconducting Behavior of MgB2 Bulks

Due to its superconducting properties, MgB
₂
materials are strategic for practical application as bulk, wire, tape, or cable. Recent work has shown that VB
₂
additions introduce effective artificial pinning centers in the MgB
₂
superconducting matrix, and an enhancement of its critical current density was observed. In this work we study the addition of NbB
₂
in the production process of MgB
₂
superconducting bulks and its influence on the superconducting behavior of the material. Different contents of additional NbB
₂
, heat treatment profiles using continuous argon flux and hot isostatic pressing, different methods to compact the bulks, and their influences on the superconducting properties of MgB
₂
are studied. As a result, the hot isostatic pressed samples reveal a denser and more homogeneous superconducting matrix. The addition of NbB
₂
introduces randomly distributed clusters of NbB
₂
in the MgB
₂
superconducting matrix, which can act as effective artificial pinning centers.