Material Specification for Bi:2223; [Bi(Pb)-Sr-Ca-Cu-O]
Process: Sintering
Notes: The authors cite W. Lo et al., J. Mater. Sci., Vol. 29, 3897 (1994), and summarize the procedure as follows. "The fabrication process essentially consists of preparing (Bi,Pb)2Sr2Ca2Cu3Ox powder, suspending the particles in a mixture of organic medium and deflocculant, aligning the particles using a magnetic field, removing the suspension medium and additives, compacting the particles by mechanical pressing, and subsequently densifying the green compact by sintering. The average size of the particles in the present fabrication process, as characterized using a particle size analyzer, is about 6 µm. The intensity of the magnetic field employed was 6 T. The particles were compacted after additive removal using cold isostatic pressing at a pressure of 400 MPa. The compacted pellet was then fired at 835 °C in air for 200 h."
Formula: Bi2-xPbxSr2Ca2Cu3Oy
Informal Name: Bi:2223
Chemical Family: Bi(Pb)-Sr-Ca-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Density (mass) for Bi:2223; [Bi(Pb)-Sr-Ca-Cu-O]
| Temperature (°C) |
Relative Density (%) |
Density (g cm-3) |
| 23 |
83 |
5.44 |
Measurement Method: Archimedes' method
"The density of the sintered pellet was measured using the immersion technique... The density of the specimen after firing was 83% of the theoretical value, assuming the theoretical density of the superconducting phase to be 6.55 g/cm
3."
Cautions: Evaluated Data
Critical Temperature for Bi:2223; [Bi(Pb)-Sr-Ca-Cu-O]
| Critical Temperature (K) |
| 108 |
Measurement Method: Ac susceptibility
"The superconducting critical transition temperature was measured using an ac magnetometer." No additional measurement details were noted.
Cautions: Unevaluated Data
Hardness for Bi:2223; [Bi(Pb)-Sr-Ca-Cu-O]
| Specimen Plane () |
Indentation Load (N) |
Hardness (GPa) |
| xy |
1.6 |
0.55 |
| xy |
0.9 |
0.46 |
| xy |
2.3 |
0.46 |
| xy |
3.3 |
0.46 |
| xy |
5.0 |
0.39 |
| xy |
9.8 |
0.42 |
| xy |
19.5 |
0.39 |
| xy |
29.4 |
0.37 |
| xy |
49.1 |
0.38 |
| yz |
1.3 |
0.53 |
| yz |
0.5 |
0.43 |
| yz |
2.2 |
0.43 |
| yz |
1.5 |
0.37 |
| yz |
3.2 |
0.36 |
| yz |
4.9 |
0.33 |
| yz |
9.7 |
0.30 |
| yz |
29.4 |
0.32 |
| yz |
49.1 |
0.33 |
Measurement Method: Vickers indentation
"Vickers indentations have been made into the textured material, on surfaces having two different orientations... Prior to the indentation study, a smooth cross section parallel to the grain alignment direction of the pellet, denoted as the z-direction,... was obtained by cutting and then polishing the pellet. In order to improve the accuracy of the indentation study on a plane perpendicular to the grain alignment direction [the xy plane...], a second surface of the pellet was also ground and polished. Vickers indentations on both surfaces were performed with loads ranging from 0.5 N to 50 N to obtain a range of indent sizes. The diagonals of the indents, and the coincidentally impressed areas below the indents thus created, were measured and characterized using high resolution scanning electron microscopy... The length of the diagonals of each indentation in both xy-plane and yz-plane was measured directly from the high resolution scanning electron micrographs. The Vickers hardness of each indentation was then calculated from the relationship:
H
= 1.85 x 103 P/d2 [GPa],
where P is the load in Newtons and d, in micrometers, is the average diagonal length of the indent."
Cautions: Evaluated Data
Digitized data were obtained from Figure 11 of the paper.
