Material Specification for Nd:123; [Nd-Ba-Cu-O]
Process: Solid State Reaction
Notes: "Powders of Nd2O3, BaCO3, and CuO were mixed in the appropriate ratios. The superconductor was synthesized by low-pressure calcination with the first calcination being 4 h at 800 °C at an oxygen partial pressure of 260 Pa, followed by regrinding and further calcination at 900 °C for 4 h in air. The final calcination was performed for 24 h at 920 °C in air. Tracer diffusion measurements are meaningful only if the sample porosity is not connected. Therefore, a final densification was performed by sinter forging in air at 920 °C to a strain of (about) 50%. The resultant specimen was over 90% of theoretical density... Samples were polished using a 0.03 µm abrasive, placed in a dry nitrogen glovebox where they were etched in a 1% solution of Br in ethyl alcohol. Samples were not exposed to laboratory air until the end of the diffusion anneal. The samples were sealed in quartz tubes under 16O for equilibrium anneals, followed by diffusion anneals in 18O, backfilled to give an oxygen partial pressure of 1 x 105 Pa at the diffusion temperature."
Formula: NdBa2Cu3O7-x
Informal Name: Nd:123
Chemical Family: Nd-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Critical Temperature for Nd:123; [Nd-Ba-Cu-O]
| Critical Temperature (K) |
| 86 |
Measurement Method: Magnetization method
"After oxygenation for 24 h at 425 °C, diamagnetic magnetization (was) measured in a (16 A/m = 0.2 Oe) field..." No additional measurement details were noted.
Cautions: Unevaluated Data
Diffusion Coefficient for Nd:123; [Nd-Ba-Cu-O]
| Diffusing Species () |
Temperature (K) |
Diffusion Time (s) |
Diffusion Coefficient (log10(cm2/s)) |
| oxygen |
400 |
3600 |
-11.6 |
| oxygen |
400 |
3600 |
-11.6 |
| oxygen |
400 |
3600 |
-11.8 |
| oxygen |
400 |
4500 |
-11.4 |
| oxygen |
500 |
1200 |
-10.4 |
| oxygen |
500 |
1200 |
-10.0 |
Measurement Method: Mass spectrometry (SIMS)
"Depth profiling was performed with a Cameca 5f secondary ions mass spectrometer (SIMS) using a 17 keV Cs
+m
beam. The negative secondary ions of interest were mass spectrographically analyzed. Corrections were made for background and the data were fitted to the solution of the diffusion equation... using a nonlinear least-squared analysis to calculate the diffusion coefficient."
Cautions: Evaluated Data
