Kinetic criteria of glass formation and the pressure dependence of the glass transition temperature

2012 ◽  
Vol 136 (7) ◽  
pp. 074512 ◽  
Author(s):  
Jürn W. P. Schmelzer
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Pressure Dependence ◽  
Glass Formation

Design rules for glass formation from model molecules designed by a neural-network-biased genetic algorithm

Soft Matter ◽  
2019 ◽  
Vol 15 (39) ◽  
pp. 7795-7808 ◽  
Author(s):  
Venkatesh Meenakshisundaram ◽  
Jui-Hsiang Hung ◽  
David S. Simmons
Keyword(s):  
Neural Network ◽  
Genetic Algorithm ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Glass Formation ◽  
Molecular Geometry ◽  
Design Model ◽  
Design Rules ◽  
Model Glass

A neural-network-biased genetic algorithm is employed to design model glass formers exhibiting extremes of fragility of glass formation, elucidating connections between molecular geometry, thermodynamics, fragility, and glass-transition temperature.

Critical Cooling Rate Vs. Reduced Glass Transition: Scaling Factors and Master Curves

1998 ◽  
Vol 554 ◽  
Author(s):  
N. Clavaguera ◽  
M. T. Clavaguera-Mora
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Cooling Rate ◽  
Glass Formation ◽  
Supercooled Liquid ◽  
High Viscosity ◽  
Master Curves ◽  
Critical Cooling Rate ◽  
Equilibrium Solidification

AbstractThe aim of the present paper is to analyse the glass formation and stability of bulk metallic glasses. Attention is focused to metallic alloys as systems which may develop a large glassforming ability. Glass formation when quenching from the liquid state is discussed in terms of the thermodynamics and kinetics of the stable/metastable competing phases. Thermodynamics is required to relate glass transition temperature, Tg, to the energetics of the supercooled liquid. Kinetic destabilisation of equilibrium solidification and, consequently, glass forming ability are favoured by the high viscosity values achieved under continuous cooling. The relative thermal stability of the supercooled liquid depends on the thermodynamic driving force and interfacial energy between each competing nucleating phase and the molten alloy. It is shown that the quantities representative of the process, once scaled, have a temperature dependence that is mostly fixed by the reduced glass transition temperature, Tgr= Tg/Tm, Tm being the melting temperature. Based on the classical models of nucleation and crystal growth, the reduced critical cooling rate is shown to follow master curves when plotted against Tgr. Experimental trends for specific systems are compared to predicted values from these master curves.

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