Abstract
The ribbons of amorphous Zr63Al7.5Cu17.5Ni10B2 alloys with 0.1 mm thickness were prepared by melt spinning method. The thermal properties and micro structural development during the annealing of amorphous alloy have been investigated by a combination of differential thermal analysis, differential scanning calorimetry, high-temperature optical microscope, X-ray diffractometry and TEM. The glass transition temperature for the Zr63Al7.5Cu17.5Ni10B2 alloys are measured about 645 K (372°C). This alloy also obtains a large temperature interval ΔTx about 63 K. Meanwhile, the calculated Trg for Zr63Al7.5Cu17.5Ni10B2 alloy presents the value of 0.57. The activation energy of crystallization for the alloy Zr63Al7.5Cu17.5Ni10B2 was about 370 ± 10 kJ/mole as determined by the Kissinger and Avrami plot, respectively. These values are about 20 % higher than the activation energy of crystallization for the Zr65Al7.5Cu17.5Ni10 alloy (314kJ/mol.). This implies that the boron additions exhibit the effect of improving the thermal stability for the Zr-based alloy. The average value of the Avrami exponent n were calculated to be 1.75 ± 0.15 for Zr63Al7.5Cu17.5Ni10B2 alloy. This indicates that this alloy presents a crystallization process with decreasing nucleation rate.
Original language | English |
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Pages (from-to) | 1867-1872 |
Number of pages | 6 |
Journal | Materials Science Forum |
Volume | 426-432 |
Issue number | 3 |
State | Published - 2003 |
Event | Thermec 2003 Processing and Manufacturing of Advanced Materials - Madrid, Spain Duration: 7 Jul 2003 → 11 Jul 2003 |
Keywords
- Bulk amorphous
- Crystallization kinetics
- Glass transition temperature
- Thermal properties
- Zirconium-based alloy