Question on parameters setting for Cu-base alloy solidification kinetics

[dhe]

Dear sir or madam,

sorry to bother you, I am currently performing a phase-field simulation of Cu-base alloy. While nucleation is successfully triggered in my simulation, I am encountering an issue with the subsequent remelting and solidification process.

Specifically, the transformation from both solid to liquid and liquid to solid is extremely slow, and the crystal growth rate appears to be much lower than expected. this behavior seems unphysical for my system and suggests that some parameters may not be properly set.

I would like to ask for your advice on which parameters I should focus on to improve the solidification kinetics. I have already try to change the kinetics coefficients in the phase intereaction parts, but still can not get what I expected.

For your reference, I have attched my driving files, ges5 file and temperature field. Any feedback on them would be highly appreciated.

Thank you very much for your time and support.

Best regards,
Dai He

[Bernd]

Dear Dai He,

Your problem comes from the diffusion coefficients: If you have a look at the .diff-output or at the .TabD-file, you see that all diffusion coefficients are zero. This automatically leads to a tiny interface mobility (see .mueS-output), because you request diffusion limited interface kinetics by using "mob_corr" together with a large input value of the (physical) mobility.

Could it be that there was an incompatibility of your mobility database, or you did not append a mobility database at all? If you do not have access to a mobility database suitable for your system, you should just define the diffusion coefficients in the liquid phase manually (e.g. 1.D-5 cm2/s for all elements). The diffusivity of the fcc-phase can be disregarded in a first step.

Best wishes
Bernd