Material Specification for Y:123; [Y-Ba-Cu-O:Ag]
Process: Solid State Reaction
Notes: "The... powder was synthesized by solid-state reaction of constituent powders of Y2O3, CuO, and BaCO3. The constituent powders were mixed in appropriate amounts and the resulting mixtures were then vacuum calcined at 810 °C for 8 h in a flowing oxygen atmosphere at a pO2 of 0.005 MPa. YBCO/Ag composite powders were made by adding 10 to 15 vol.% of Ag powder to the YBCO powder... In making the wires, YBCO and Ag/YBCO powders were mixed with appropriate solvent, dispersant, binder, and plasticizer to form appropriate slips, which were then forced through a die to produce wire (45 mils or 1.14 mm diameter). The extruded wires were heat treated in a predetermined schedule with three stages: binder-burnout (240 °C), densification (910-950 °C), and oxygen annealing (450 °C). The rectangular bars (4.3 cm x 0.8 cm x 0.4 cm) were pressed at 172 MPa and subsequently sintered at 910 °C to 930 °C and then annealed in flowing oxygen at a pO2 of 0.1 MPa (1 atm) at 450 °C for 6 h."
Formula: YBa2Cu3O7-x•yAg
Informal Name: Y:123
Chemical Family: Y-Ba-Cu-O:Ag
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Flexural Strength for Y:123; [Y-Ba-Cu-O:Ag]
| Volume Fraction of Ag (%) |
Sintering Temperature (°C) |
Sintering Time (h) |
Oxygen Pressure (MPa) |
Flexural Strength (MPa) |
| 0 |
910 |
10 |
0.100 |
120 ± 10 |
| 0 |
925 |
10 |
0.100 |
141 ± 9 |
| 0 |
935 |
12 |
0.100 |
91 ± 7 |
| 0 |
935 |
20 |
0.100 |
95 ± 6 |
| 0 |
950 |
20 |
0.100 |
83 ± 5 |
| 0 |
910 |
10 |
0.001 |
191 ± 7 |
| 15 |
900 |
10 |
0.001 |
225 ± 6 |
Measurement Method: Three-point bend
"Strength of the wires was measured in a three-point bending mode with a support span of 1.825 cm and a crosshead speed of 0.127 cm/min." No additional measurement details were noted.
Cautions: Evaluated Data
"...the density of monolithic YBCO wires increased from 79 to 98% of theoretical when sintering temperature was increased from 910 to 950°C. However, this density increase was associated with a corresponding increase in average grain size from 4 to 23 µm. The increased grain size has a deleterious effect on the strength of YBCO, which declines from 120 MPa for specimens sintered at 910°C with an average grain size of 4 µm to 83 MPa for specimens sintered at 950°C with an average grain size of 23 µm. The increase in flextural strength of specimens sintered at 910°C (pO
2 = 0.1 MPa) is believed to be due to the decreased grain size relative to that of specimens sintered at 950°C; this confirms the inverse dependence of strength on grain size....a decrease in pO
2 from 0.1 to 0.001 MPa resulted in a corresponding increase in density from 79 to 91% theoretical for specimens sintered at 910°C for 10 h, while grain size remained at 3-5 µm. This increase in density further increased strength from 120±10 to 191±7 MPa."
Fracture Toughness for Y:123; [Y-Ba-Cu-O:Ag]
| Volume Fraction of Ag (%) |
Sintering Temperature (°C) |
Sintering Time (h) |
Oxygen Pressure (MPa) |
Fracture Toughness (MPa·m1/2) |
| 10 |
900 |
12 |
0.001 |
3.3 ± 0.2 |
Measurement Method: Single-edge notched beam
The authors cite W.F. Brown, Jr. et al., Plane Strain Crack Toughness Testing of High Strength Metallic Materials, Special Technical, Publication No. 410, ASTM (1966) 13, and summarize the procedure as follows. "Fracture toughness of the bar specimens was measured by a single-edge-notch beam technique."
Cautions: Evaluated Data
