MICRESS Forum

Hi.
Is there any physical significance for the interfacial energy used in Micress? For example, if I take the gamma-alpha example, the value used is 2 J/m^2, which is close to the interfacial energy of a coherant interface. Can we really consider it like this(since we tell coherant interface mostly for only precipitate nucleation). Is there any other physical significance for this term, or is this just a numerical parameter. If its a numerical parameter, how can we make a 'wise guess' of the starting value for this parameter?

Thanks,
Deepu

Hi deepumaj1,

The interfacial energy has a very important role in microstructure formation, because it is responsible for the curvature undercooling and thus determines the microstructure length scale. The same is the case with MICRESS. As long as the simulation is not 1D or the interface is completely flat, the value of the interfacial energy determines the amount of the curvature undercooling.

Apart from this physical meaning, the interfacial energy in MICRESS also stabilizes the interface profile. Thus, if you would use a value of 0 or almost 0, the interface would break apart. This numerical role of the interfacial energy can be (partly) replaced or enhanced by using an extra "interface stabilisation" energy.

Thus, if you assume the gamma-alpha interface to be coherent, it could have a relatively small interface energy. But this would have consequences for the gamma-alpha transformation and should be visible in corresponding experiments.