| Autor: |
Suan, M. S. M., Johan, M. R. |
| Zdroj: |
Materials Research Innovations; Dec2014 Supplement, Vol. 18, pS6-73-S6-77, 5p |
| Abstrakt: |
The effects of Al2O3 nanoparticles on the phase formation, microstructure and microhardness of YBa2Cu3O7-δ superconductor prepared by citrate-nitrate auto-combustion reaction were investigated. In this study, YBa2Cu2O7-δ precursor gels containing different compositions of Al nitrate varied from 0.02 to 0.10 mol were continuously heated at 250 °C before automatically combusted into very fine ashes. Calcination process at 900 °C for 1 h has transformed these ashes into sample powders. The XRD and EDX results revealed that Al2O3 nanoparticles were yielded as separate phase from YBa2Cu3O7-δ. The nanoparticles were observed homogeneously distributed in ≤ 0.06 mol samples while agglomerated along YBa2Cu3O7-δ grain boundaries in other samples. The 0.06 mol sample has the highest microhardness compare with the other samples. The Al2O3 nanoparticles by ≤ 0.06 mol compositions were effectively acted as reinforced phase which prevent further dislocation movements of YBa2Cu3O7-δ grains. As for ≥0.06 compositions, agglomeration of Al2O3 nanoparticles may introduce ductility. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
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