Phase transformations, driving forces for

Magnetic effects on metastable transformations. The underlying factor in all the above effects is the magnitude of the ratio (G" /G ° ) and especially its variation with temperature. It follows that there can also be a substantial effect on the driving force for phase transformations, including shear transformations. Thus the martensite start temperature, in most Fe alloys is dominated by the... 

When examining the kinetics of a phase transformation, a typical first step is to calculate the thermodynamic driving force for the process. Consider again the water/ice example above. At equilibrium T=T = 0 °C), the thermodynamic driving force for transformation is zero. However, if the temperature is displaced from this equilibrium temperature, the balance will be upset and a thermodynamic driving force for phase transformation will ensue. How can we quantify this driving force ... 

Thus, the larger the degree of supercooling below (or superheating above) the equilibrium temperature, the larger the driving force for phase transformation. 

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