ISSN:
1572-9605
Keywords:
Bi2223 tapes
;
grain orientation
;
critical current density
;
microstructure
Source:
Springer Online Journal Archives 1860-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
Abstract For polycrystalline Ag/Bi-2223 tapes, the preferential orientation of grains is a very important issue. The platelike grains in the tapes are generally believed in a high-order alignment. However, microstructural observation by SEM shows that the grain alignment is far from perfect. Theoretically, upper critical field, H c2, for H parallel to ab plane and c axis was calculated form the relation of M(H). However, the ratio of H c2 (H//ab) to H c2(H//c) depends on the angle (θ) between the ab plane of grains and the broad surface of the tapes. Based on the ratio, the orientation distribution of grains is obtained. The results show that grains in Ag/Bi-2223 tapes can grow with ab plans at any angle between 75° 〉 θ 〉 −75°, but no grain can grow with its ab plane perpendicular to the tape broad surface. The overall distribution is that: 〉90% grains orient in the angle range of |θ| 〈 ± 75°, about 5% grains at ±75° ≤|θ| ≤ ±85°, and no grains at |θ| 〉 ±85°.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007711310818
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