Influence of particle shape anisotropy and ductility under uniaxial force during fabrication on the structure of polycrystalline MgB2 superconductors

• Using shape-anisotropic powders does not severely reduce the density of MgB2 bulk. • Proper utilization of shape-anisotropic powders can even enhance the bulk density. • Powder shape anisotropy has little effect on void elongation in the MgB2 wire core. • Proper utilization of shape-anisotropic powders can even improve the transport Jc. Polycrystalline materials for use in research and industry are often fabricated using powder filling and forming techniques. Since the resulting structures formed through powder-based fabrication depend on particle properties (e.g., size, shape, and ductility), a deeper understanding of the effects of these properties is essential for advancing material development. We focus on the shape anisotropy of particles and its influence on MgB 2 materials in this study. Anisotropic particles are obtained by microscopic deformation of ductile Mg that occurs during mechanical mixing. The use of deformed particles with anisotropic shapes positively impacts the mass density of MgB 2 materials. The anisotropic particles also tend to align roughly in a preferred direction during material processing under a uniaxial force. This alignment tendency can be utilized to control the void orientation induced by anisotropic particles in polycrystalline materials. These results provide insights into how particle shape anisotropy and ductility affect the material structure formed through powder-based fabrication. The structural findings presented here will be useful in developing various powder-based materials, including polycrystalline MgB 2 superconductors.