Kinetics of Phase Separation in Lithium Bearing HLW Alkaliborosilicate Glasses

1995 ◽  
Vol 412 ◽  
Author(s):  
J. GÖttlicher ◽  
H. J. Pentinghaus
Keyword(s):  
Phase Separation ◽  
Transformation Temperature ◽  
Ostwald Ripening ◽  
Metastable Phase ◽  
Particle Growth ◽  
Glass Frit ◽  
Diffusion Controlled ◽  
Metastable Phase Separation ◽  
Scale Particle ◽  
Kinetics Of

AbstractA TEM study on the kinetics of metastable phase separation in a lithium bearing HLW glass frit is presented. As nothing was known about the kinetics of metastable phase separation below the glass transformation temperature we had to carry out annealing experiments just above and below the transformation temperature, in order to achieve phase separation on a laboratory time scale- Particle growth in the WAKID5 HLW glass frit at 550 °C occurs by a diffusion controlled Ostwald ripening process (about 40 °C above Tg). Metastable phase separation in the lithium bearing glasses even at lower temperatures cannot be excluded from the present study. In NaBSi3O8 glass (Tg ≈ 580 °C) phase separation could be detected at 500 °C well below Tg after about 160 days.

Refinement of Size Distributions for Primary Crystallizations

1997 ◽  
Vol 481 ◽  
Author(s):  
E. Pineda ◽  
T. Pradell ◽  
D. Crespo ◽  
N. Clavaguera ◽  
J. ZHU ◽  
...  
Keyword(s):  
Grain Size ◽  
Metastable Phase ◽  
Primary Crystallization ◽  
Controlled Growth ◽  
Diffusion Controlled ◽  
Average Grain Size ◽  
Soft Impingement ◽  
Single Grain ◽  
Kinetics Of ◽  
And Diffusion

ABSTRACTThe microstructure developed in primary crystallizations is studied under realistic conditions. The primary crystallization of an amorphous alloy is modeled by considering the thermodynamics of a metastable phase transition and the kinetics of nucleation and crystal growth under isothermal annealing. A realistic growth rate, including an interface controlled growth at the beginning of the growth of each single grain and diffusion controlled growth process with soft impingement afterwards is considered. The reduction in the nucleation rate due to the compositional change in the remaining amorphous matrix is also taken into account. The microstructures developed during the transformation are obtained by using the Populational KJMA method, from the above thermodynamic and kinetic factors. Experimental data of transformed fraction, grain density, average grain size, grain size distribution and other related parameters obtained from annealed metallic glasses are modeled.

Observation of metastable phase separation and amorphous phase in Fe67Co33 alloy thin films synthesized by pulsed laser depositions

2015 ◽  
Vol 15 (6) ◽  
pp. 717-721 ◽  
Author(s):  
G. Hassnain Jaffari ◽  
Abdul K. Rumaiz ◽  
C. Ni ◽  
Emre Yassitepe ◽  
M. Bah ◽  
...  
Keyword(s):  
Thin Films ◽  
Phase Separation ◽  
Amorphous Phase ◽  
Metastable Phase ◽  
Pulsed Laser ◽  
Metastable Phase Separation
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