Material Specification for Y:123; [Y-Ba-Cu-O]
Process: Solid State Reaction
Notes: The authors cite A. Goyal et al., Physica C, Vol. 182, 203 (1991), and summarize the procedure as follows. "Highly aligned 123 and 123-Ag composites were prepared using a liquid phase processing technique... The samples employed for this study consisted of several domains or pseudo crystals as large as 5-6 mm long and 4-5 mm wide. Each of these domains is made up of a stack of highly aligned platelets approximately 10 µm in width... Samples were cut in a direction perpendicular to the clevage surface [i.e., (010)/(100)] and sections of both the clevage surface and the section perpendicular to the cleavage surface were mounted using standard metallographic procedures."
Formula: YBa2Cu3O7-x
Informal Name: Y:123
Chemical Family: Y-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Hardness for Y:123; [Y-Ba-Cu-O]
| Crystal Plane () |
Hardness (GPa) |
| (001) |
6.71 ± 0.02 |
| (100/010) |
3.8 |
Measurement Method: Vickers indentation
"The samples were ultrasonically machine polished with a 0.5-µm abrasive in an oil-based medium to prevent any reaction with water. The load applied during polishing was even and kept to a very low level to minimize the formation of surface residual stresses. Indentations on well-polished surfaces were made with a Shimadzu hardness tester, using a Vickers Diamond Pyramid indentor in ambient air at room temperature. Contact loads between 0.1 N and 2 N for a peak load contact time of 10 s were used... For indentations made on the (001) cleavage surface, the diagonals of the impression were aligned in a direction nearly coincident with the [100] and the [010] directions. Indentations on the section perpendicular to the clevage surface were made with the impression diagonals parallel and perpendicular to the trace of the (001) platelet boundaries on the polished section."
Cautions: Evaluated Data
Fracture Toughness for Y:123; [Y-Ba-Cu-O]
| Crystal Plane () |
Fracture Toughness (MPa·m1/2) |
| (001) |
0.67 |
Measurement Method: Vickers indentation
"The samples were ultrasonically machine polished with a 0.5-µm abrasive in an oil-based medium to prevent any reaction with water. The load applied during polishing was even and kept to a very low level to minimize the formation of surface residual stresses. Indentations on well-polished surfaces were made with a Shimadzu hardness tester, using a Vickers Diamond Pyramid indentor in ambient air at room temperature. Contact loads between 0.1 N and 2 N for a peak load contact time of 10 s were used... For indentations made on the (001) cleavage surface, the diagonals of the impression were aligned in a direction nearly coincident with the [100] and the [010] directions. Indentations on the section perpendicular to the clevage surface were made with the impression diagonals parallel and perpendicular to the trace of the (001) platelet boundaries on the polished section."
Cautions: Evaluated Data
"In order to determine K
c an estimate of the modulus/hardness ratio, E/H, is needed. ... the modulus in the a/b direction of 182 GPa was used to determine the fracture toughness for indentations on the (001) basal plane. This gives an E/H ratio of (about) 27."
