REBa₂Cu₃O_y (REBaCuO) superconducting bulk materials, where RE denotes Yttrium and rare-earth elements, are subjected to electromagnetic force and thermal stress in devices. As the bulk size and critical current increase, these forces and stresses also rise, making the improvement of mechanical properties, such as fracture strength, crucial for developing high-performance superconducting devices. REBaCuO bulk materials, which are single-grain, are typically fabricated through melt-processing using a seed crystal. Conventional REBaCuO bulk materials often contain pores that degrade mechanical properties. However, a new fabrication technique, called the infiltration growth technique, can produce REBaCuO bulk materials with low porosity.  The mechanical properties of REBaCuO bulk materials fabricated using the infiltration growth technique have not been extensively investigated. In this study, tensile tests were conducted on specimens cut from YBaCuO bulk material fabricated by the infiltration growth technique to evaluate their mechanical properties. The effects of porosity on mechanical properties were examined in relation to the fracture mechanism.

Keywords: YBaCuO, Single-Grain bulk, Infiltration growth, Mechanical properties