Search found 84 matches

by zhubq
Sat Feb 02, 2013 12:15 am
Forum: solid-solid phase transformations
Topic: Artifact?
Replies: 12
Views: 4069

Re: Artifact?

Hi Bernd. Previously I thought in NPLE model, the concentration of slow-diffusing elements within the interface is forced to the equilibrium values (NPLE tie line in the phase diagram) and the driving force is only contributed by the fast-diffusing elements e.g. C since only their concentrations are...
by zhubq
Wed Jan 30, 2013 8:45 pm
Forum: solid-solid phase transformations
Topic: Artifact?
Replies: 12
Views: 4069

Re: Artifact?

Hi Bernd, Obviously a positive spike in austenite should be there during austenite-to-ferrite transformation. However, here is ferrite-to-austenite transformation. A negative spike i.e. a valley exists in ferrite while the Mn in austenite--the growing phase should equal Mn0. Therefore, this simulati...
by zhubq
Wed Jan 30, 2013 4:03 am
Forum: solid-solid phase transformations
Topic: Artifact?
Replies: 12
Views: 4069

Artifact?

Hi Bernd, Attached figure is the phase concentration (extracted from file e.g. *.c2Pha3) since in the phase field model, the solute concentration follows C=f1*C1+f2*C2, where f1,f2 is the fraction of each phase and C1, C2 is solute concentration in each phase, there will be a concentration gradient ...
by zhubq
Tue Oct 30, 2012 7:04 am
Forum: thermodynamics
Topic: ThermoCal coupled problem, NPLE and no_TQ problem
Replies: 7
Views: 3685

Re: ThermoCal coupled problem, NPLE and no_TQ problem

Hi Bernd, I wanna add some questions here for my simulations.[ I used micress 4.08a. unfortunately cannot use newest version 6.003 in our institute.] 1) the linearisation parameters obtained in a TQ coupled simulation depend on the input of initial concentration of each phase even when the fraction ...
by zhubq
Wed Oct 24, 2012 10:32 pm
Forum: thermodynamics
Topic: NPLE
Replies: 7
Views: 3736

Re: NPLE

Hi Bernd,

It would be quite appreciated if you could send me the example (zhubenqiang@gmail.com).
The line between C2 and C3 is isoactivity line for carbon.
You can see the schematic of LENP below.
by zhubq
Tue Oct 23, 2012 11:27 pm
Forum: thermodynamics
Topic: NPLE
Replies: 7
Views: 3736

Re: NPLE

Hi Bernd, I have one question that with an extremely high mobility, the solute concentrations will approach to the equilibrium which are C1 and C2 in the attached figure. But the carbon concentration near the interface edge should be C3 which is a little bit different from C2 in terms of the Carbon ...
by zhubq
Tue Oct 23, 2012 11:01 am
Forum: thermodynamics
Topic: NPLE
Replies: 7
Views: 3736

Re: NPLE

Hi, Bernd. Thank you for quick reply. Here is my understanding: 1)to simulate nple conditions e.g. in Fe-C-Mn alloy, chose C as "diff" and "normal" while Mn as "no_diff" and "nple"; the thermodynamic data e.g. del_S and slopes, are the same as ortho equilibrium condition. 2) the Mn concentration in ...
by zhubq
Sat Oct 20, 2012 12:51 am
Forum: thermodynamics
Topic: NPLE
Replies: 7
Views: 3736

NPLE

Hi Bernd, I found MICRESS has a model for NPLE. But there is no document detailing it. The only literature is "J Rudnizki et al. phase-field modeling of austenite formation from a ferrite plus pearlite microstructure during annealing of cold-rolled dual-phase steel. Metal Mater Trans. 2011". Could y...
by zhubq
Tue Apr 24, 2012 12:43 am
Forum: thermodynamics
Topic: entropy difference between two phases
Replies: 16
Views: 7033

Re: entropy difference between two phases

Hi, Bernd. If I want to use Thermo-Calc to get the entropy between two phases for linearized para phase diagram, what should I do? As you mentioned, I should fix the composition of one phase and change the temperature to find out the driving force at various temperatures. But how do I find out the c...
by zhubq
Sun Jan 08, 2012 10:44 pm
Forum: thermodynamics
Topic: thermodymics problem
Replies: 3
Views: 2343

Re: thermodymics problem

Bernd. So far I have not seen any negative value in my simulation. But what do you think about the interface concentration configuration if the temperature is in a single phase region when people talk about using an extremely high mobility such that the interface is diffusion controlled. Because if ...