Fracture toughness measurements of YBa2Cu3Ox single crystals

Abstract

We report fracture toughness measurements on single crystals of YBa2Cu3Ox, the phase responsible for superconductivity above liquid-nitrogen temperatures. Indentation crack length measurements on the (010) orthorhombic crystal growth faces revealed the (100) and (001) planes as preferred fracture planes. The toughness of these planes is Kc=1.1±0.3 MPa m1/2, and the hardness H=8.7±2.4 GPa. The observed growth of both radial and lateral cracks in ambient air suggests that these crystals are susceptible to moisture-enhanced nonequilibrium crack propagation.

Mechanical Properties of<tex>$rm Y$</tex>123/<tex>$rm Ag$</tex>Superconducting Bulks

“…Mechanical properties in highoxide superconductors, such as flexural strength, fracture toughness and ductility are very crucial for industrial applications, as well as , and of the superconductors. Oxide superconductors have the intrinsic brittleness due to the perovskite structure, thus, the strength and the fracture toughness of the materials are low and anisotropic [5]- [10]. Therefore, it is very important to study Manuscript and improve the mechanical properties of the oxide superconductors for applications.…”

Stress–strain behavior under static loading in Gd123 high-temperature superconductors at 77K

“…Microstructures of RE123 melt-processed bulks and those of RE123 materials of HTS conductors are similar to each other in that both of them have single-grained matrices, although the composition and size of the secondary phase are different from each other [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. For example, melt-processed bulks consist of RE123 matrix and RE 2 BaCuO 5 (RE211) secondary phase particles.…”

The contribution of 211 particles to the mechanical reinforcement mechanism of 123 superconducting single domains

“…This result lies between the Y-123 single-crystal hardness value in the same planes (8.7GPa) [31] and the hardness value reported for Y-123 polycrystalline samples (5GPa) [32].…”