کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1492402 | 992380 | 2006 | 10 صفحه PDF | دانلود رایگان |
A mixed alkali germano-phosphate glass composition (Li0.5Na0.5Ge2(PO4)3) has been prepared and characterized. The crystallization mechanism of a NZP-type phase, the nucleation rate and the non-isothermal kinetic parameters have been studied by differential thermal analysis (DTA).The plot of the DTA peak height versus the glass particle size has shown a great tendency for surface crystallization. The nucleation rate type curves have given a maximum at 465 ± 2 °C and confirmed that nucleation was instantaneous at this temperature. Furthermore, the average value of the Avrami exponent (5.4 ± 0.4) has revealed a tri-dimensional growth controlled by the development of the glass–crystal interface with a decreasing nucleation rate in the temperature range explored. From non-isothermal experiments, the apparent activation energy for the overall crystallization phenomenon has been founded in the range 260–273 kJ/mol whereas the activation energy for crystal growth was 488 ± 6 kJ/mol.
Journal: Materials Research Bulletin - Volume 41, Issue 7, 13 July 2006, Pages 1249–1258