Mechanical properties of TSMG-YBCO

The fracture toughness, K-C of YBCO prepared by the top-seeded-melt-growth (TSMG) method ran be improved by increasing the yttrium content. K-C increa ses from 1.01 MPa root m for samples with 30 mol % Y2Ba1Cu1O5 (Y-211) addit ion to a value of 1.44(22)MPa root m for samples with 60 mol % Y-211 additi on. Substituting CeO2 for PtO2 results in a further enhancement of K-C In b oth cases the improvement can be explained by a refinement and homogenizati on of the distribution of Y-211 particles. The incorporation of ductile par ticles also contributes to an enhanced fracture toughness of the melt-textu red monoliths.