Search found 1085 matches

by Bernd
Tue Nov 12, 2019 5:57 pm
Forum: recrystallisation/grain growth
Topic: how to turn off the Gibbs-Thomson effect
Replies: 7
Views: 61

Re: how to turn off the Gibbs-Thomson effect

Dear Sai Li, I think it is important in such a complex system not only to think of local equilibria at the interfaces, but also of kinetics. If we assume that the models I and II like you sketched them represent an initial microstructure in MICRESS, and temperature is chosen slightly above the globa...
by Bernd
Thu Nov 07, 2019 12:41 pm
Forum: solidification
Topic: Directional solidification of Al-Si hypoeutectic alloy
Replies: 9
Views: 124

Re: Directional solidification of Al-Si hypoeutectic alloy

Hi Yuta,

I fully agree!

Bernd
by Bernd
Thu Nov 07, 2019 12:36 am
Forum: solidification
Topic: Directional solidification of Al-Si hypoeutectic alloy
Replies: 9
Views: 124

Re: Directional solidification of Al-Si hypoeutectic alloy

Hi Yuta,

Yes, interface stabilisation is correct like you say. Please try out whether it is helpful for you, it depends a bit on the circumstances...

You are also right with the units of the interface mobility :?

Bernd
by Bernd
Sun Nov 03, 2019 8:23 pm
Forum: recrystallisation/grain growth
Topic: how to turn off the Gibbs-Thomson effect
Replies: 7
Views: 61

Re: how to turn off the Gibbs-Thomson effect

Dear Sai Li,

Your description indeed is unclear - can you show the outputs for the concentration distributions, or some sketch which clarifies your setup and what you observe?

Bernd
by Bernd
Tue Oct 29, 2019 11:13 pm
Forum: recrystallisation/grain growth
Topic: how to turn off the Gibbs-Thomson effect
Replies: 7
Views: 61

Re: how to turn off the Gibbs-Thomson effect

Dear Sai Li, How you describe it, it does not make sense! If the Gibbs-Thomson effect would be the (direct) culprit, it would increase the carbon composition rather than decreasing it! However, it may be an indirect effect: Gibbs-Thomson changes the composition of another element, and this gradient ...
by Bernd
Mon Oct 28, 2019 10:20 pm
Forum: recrystallisation/grain growth
Topic: how to turn off the Gibbs-Thomson effect
Replies: 7
Views: 61

Re: how to turn off the Gibbs-Thomson effect

Dear Sai, I don't know why you want to do that, but it is not possible without changing physics! The most logical procedure would be to set the interface energy to 0. However, this would completely destroy the stability of the interface. The best you can do is to reduce interfacial energy to a certa...
by Bernd
Mon Oct 28, 2019 10:04 pm
Forum: solidification
Topic: Directional solidification of Al-Si hypoeutectic alloy
Replies: 9
Views: 124

Re: Directional solidification of Al-Si hypoeutectic alloy

Hi Yuta, Si-particles nucleate at the liquid-fcc interface, but get rapidly overgrown. This is the reason you find them inside fcc. Possible causes are a too low undercooling, too high curvature undercooling, too low spatial resolution, or other numerical issues. The outputs at irregular intervals a...
by Bernd
Fri Oct 25, 2019 8:20 pm
Forum: solidification
Topic: Directional solidification of Al-Si hypoeutectic alloy
Replies: 9
Views: 124

Re: Directional solidification of Al-Si hypoeutectic alloy

Hi Yuta, I will comment along your points: 1.) The issue with old and new syntax is just a formal thing and has nothing to do with functionality. Therefore, it is not important whether you use old or new syntax, as long as MICRESS still supports old syntax. The new syntax rules are indicated at the ...
by Bernd
Thu Oct 24, 2019 8:21 pm
Forum: solidification
Topic: Directional solidification of Al-Si hypoeutectic alloy
Replies: 9
Views: 124

Re: Directional solidification of Al-Si hypoeutectic alloy

Hi Yuta, Welcome to the MICRESS forum! Let me try to give you answers along your questions. If you have follow-up questions, please don't hesitate to ask again in this topic! 1. Of course you can apply a .GES5 file which does not have mobility data inside. In this case, you must define diffusion dat...
by Bernd
Thu Oct 24, 2019 1:01 pm
Forum: solidification
Topic: Liquid diffusivity from database - pros and cons
Replies: 0
Views: 40

Liquid diffusivity from database - pros and cons

Hi all, Lately I have been asked several times about whether in solidification simulations one should use diffusion data for the liquid phase from database or not. More and more commercial mobility databases now contain meaningful data for this phase, like e.g. MOBNI5 or MOBFE4. The most important i...