Distribution of mechanical properties in large single-grained RE–Ba–Cu–O bulk 150 mm in diameter fabricated using RE compositional gradient technique

• Single-grained RE-Ba-Cu-O bulk 150 mm in diameter was fabricated.
• Mechanical properties have been investigated through bending tests.
• Mechanical properties of the large bulk were comparable to those of smaller bulks.

Large single-grained Gd–Ba–Cu–O high temperature superconducting (HTS) bulk 150 mm in diameter with a compositional gradient of Dy was fabricated by employing the RE compositional gradient technique and its mechanical properties have been investigated through bending tests. Two types of specimens were cut from the bulk: one type was across the boundaries between adjacent layers of the rare-earth compositional gradient and the other was not across them. No large differences were observed for the mechanical properties between two types of specimens. Furthermore, the mechanical properties of the 150 mm HTS bulk were comparable to the ones reported for smaller bulks such as 30 and 46 mm. These results demonstrate that the compositional gradient causes no significant deterioration of the mechanical properties in spite of a large dimension of 150 mm.