Not getting any solidification

[CharMIC]

Hej,

I am not getting any solidification after I increase the number of elements in the simulation. The simulation work fine with 4 elements. But now I have 8 elements. I have made necessary changes for to simulate the 7 elements (eg. GES5 file, Initial equilibrium, concentration data and the diffusion data for the elements in the liquid phase etc.)

Any input on how to debug the issue?

BR
Chamara

[deepumaj1]

Dear Chamara,
Could you please give some more details about your simulation? Is this topic a continuation of some of your other posts?

Depending on your system, your melting temperature can change based on the elements you consider (There will be changes in the phase diagram). Its always a good practice to look at your equilibrium data and see what the meting point (Freezing point in this case) for the composition considered. Based on this idea, you can decide the undercooling parameters that you need to give.

Are you doing the solidfication with 'nucleation data', or with 'grain input'? And have you checked if your solid phase is dissolving back?

Best Wishes,
Deepu

[CharMIC]

Hi Deepu

Its a simulation of directional solidification of Ni alloy.

I have taken the initial equilibrium temperature based on the Thermo-calc simulation.

In my simulation I start with grain input.

And How can I check whether my solid phase is dissolving back?


BR
Chamara

[deepumaj1]

Hi. To check if your solid is dissolving back, you can use the screen output or the log file. Look if you see for a message that looks something like 'Phase * disappeared', where * is your phase number. Alternately, you can also look at your TabF output to see if the volume fraction of your solid phase is reducing to zero.

[CharMIC]

Hi Deepu,

Thanks a lot for your inputs.

I don't see any phases dissolving back. The phase fraction is almost constant.

BR
Chamara

[Bernd]

Hi Chamara,

I think the approach of Deepu is a good one. The question is whether there is a driving force for growth. Besides the .log you should also check the .driv output. If there is sufficient driving force (i.e. a sufficiently high negative value in the .driv output), it could be due to the interface mobility (check .mueS output). Otherwise it would be a thermodynamic problem.

Bernd

[deepumaj1]

Hello Chamara,
Based on your inputs above, here is a suggestion:
Normally in Micress, when you change your elements (composition), your interfacial mobility will need a tune up. In your case, one possibility is that your interfacial mobility may not be good enough to develop the sufficient driving force for the solid to grow. You can judge this with the help of 'driv' output file and here is a link to the post that can help you in this (http://board.micress.de/viewtopic.php?f ... t%3D25#p62).

Is your simulation isothermal?

Cheers,
Deepu

[deepumaj1]

Hello Bernd,
I missed out your reply above.

Warm Regards,
Deepu

[Bernd]

Hi Deepu,

I shouldn't have stepped in, you are on the right way

Best wishes

Bernd

[deepumaj1]

Hello Bernd,
No problem. Thanks for your appreciation above.

Deepu.