https://en.wikipedia.org/wiki/Phase_diagram
https://es.wikipedia.org/wiki/Diagrama_de_fase

ASM-Phase-Diagrams-Understanding-the-Basics.pdf (Scribd)
There are: degree of attainment, degree of freedom, probable degree of solid solubility, degree of covalent or ionic bonding, degree of undercooling, degree of completion, degree of absolute temperature (T), ***degree of ordering or clustering .....***

Hence, the direction of change can be ascertained from the phase diagram, and a wealth of experience is available to indicate the probable degree of attainment of equilibrium under various circumstances.

How can there be only one degree of freedom when it is evident that both
temperature and pressure must change in order to proceed from point 2 to
point 2', where the two phases continue to exist? The answer is that only
one of the variables can be changed independently.

If the size factor is favorable, then the other three rules
should be evaluated to determine the probable degree of solid solubility.
Metallic systems that display complete solid solubility are quite rare, with
the copper-nickel system being the most important

When the electrochemical properties of the alloying element metals are
similar, normal substitutional solid solutions will form during solidification. However, when the metals have widely divergent electrochemical
properties, they are more likely to form a chemical compound, often with
some degree of covalent or ionic bonding present.

Very large undercoolings and highly polished molds are required to
cause homogenous nucleation, and it is rarely, if ever, observed in practice. In reality, the degree of undecooling is usually very small, often only
a degree or two.

The rate of transformation and the time required for the transformation
to proceed to some degree of completion are inversely proportional to one
another. The time to reach a 50% degree of completion in the reaction is
frequently used.

The entropy, S, represents the energy (per degree of absolute temperature, T> in a system that is not available for work. In terms of entropy, the
Second Law states that all natural processes tend to occur only with an
increase in entropy, and the direction of the process is always such as to
lead to an increase in entropy. For processes taking place in a system in
equilibrium with its surroundings, the change in entropy is defined as:

In systems with E < 0, the internal energy of the system is
reduced by increasing the number of A-B bonds, that is, by ordering the
atoms as shown in Fig. 3.18(a). If E > 0, the internal energy can be reduced
by increasing the number of A-A and B-B bonds, that is, by the clustering of the
atoms into A-rich and B-rich groups (Fig. 3.18b). *****However, the
degree of ordering or clustering ***** will decrease as temperature increases due
to the increasing importance of entropy. In systems where there is a size
difference between the atoms, the quasi-chemical model will underestimate the
change in internal energy on mixing, because no account is taken
of the elastic strain fields that introduce a strain-energy term into AHmix.
When the size difference is large, this effect can dominate over the chemical term.
When the size difference between the atoms is very large, then
interstitial solid solutions are energetically most favorable (Fig. 3.18~). In
systems where there is strong chemical bonding between the atoms, there
is a tendency for the formation of intermetallic phases. These are distinct
from solutions based on the pure components because they have a different
crystal structure and may also be highly ordered.

Found it. HTH.


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Note added at 36 mins (2019-03-09 16:11:29 GMT)
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Oops. Sorry, degree OF ordering or clustering.

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Note added at 10 days (2019-03-20 12:09:02 GMT) Post-grading
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Thank you Timothy.