Phase transformations
There are so many phase changes in iron
and its alloys that it is possible to generate a seemingly infinite
variety of microstructures and properties. This complexity makes
the alloys versatile but at the same time difficult to understand
and design from first principles. Much of our energy is devoted
to the development of solid-state phase transformation theory,
and its experimental validation, in the hope of inventing new
alloys and processes.
Theory of transformations
We deal mostly with phase changes which
are thermodynamically of first order, i.e. they involve nucleation
and growth with well-defined mechanisms of transformations and
particular constraints to the achievement of equilibrium. In
fact, most useful microstructures are far from equilibrium so
we build kinetic theory to determine non-equilibrium states.
There are complications when many different transformations occur
together, complications which have stimulated new theory. Finally,
the microstructure must be related to properties which are appreciated
by technologists.
Mathematical models
We express the theory and empirical observations
in the form of computer models which can be used to greatly reduce
the vast number of parameters that have to be controlled during
the creation of new alloys and processes. We also produce courses,
books and algorithms in addition to research papers to help spread
the word about this thriving science of materials.
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