Microstructure and phase development in melt processed Tl-1223 tapes
The effect of processing conditions on microstructure and phase development has been investigated for TlBi-1223 tapes made by a melt processing route. Increasing loss of crystallinity and phase decomposition into Tl-1212 and SrCaCu-oxides is seen for melt temperatures in the range 910-925°C. The 122...
| Main Authors: | , , , , , , |
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| Format: | Journal article |
| Published: |
1997
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| Summary: | The effect of processing conditions on microstructure and phase development has been investigated for TlBi-1223 tapes made by a melt processing route. Increasing loss of crystallinity and phase decomposition into Tl-1212 and SrCaCu-oxides is seen for melt temperatures in the range 910-925°C. The 1223 phase is reformed during a slow cool and subsequent annealing. It has been established that for samples of composition (Tl0.78Bi0.22)(Sr0.8Ba0.2) 2Ca2Cu3Oδ a melt temperature of around 9250C and a cooling rate of 20°C/h results in a much increased grain size of up to 60-70 μm. Use of fully reacted 1223 powder was found to result in a larger increase in grain size and better phase purity than a partly reacted precursor. © 1997 Elsevier Science B.V. |
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