Search found 31 matches
- Wed May 25, 2016 9:11 am
- Forum: solid-solid phase transformations
- Topic: Incipient melting of NbC in a nickel-matrix
- Replies: 9
- Views: 5612
Re: Incipient melting of NbC in a nickel-matrix
Dear Bernd, from a first fast test, I can see that using avg 1.0 max 100 smooth 45.0 is infact stabilizing the interface. I have to check your suggested dimension / time issues. However, also with these options there is a negative driving force at 45°, ... and a positive driving force at 90°, ... be...
- Tue May 24, 2016 4:35 pm
- Forum: solid-solid phase transformations
- Topic: Incipient melting of NbC in a nickel-matrix
- Replies: 9
- Views: 5612
Re: Incipient melting of NbC in a nickel-matrix
Hello, coming back to this topic I am wondering about the following effect: I am simulating a MC-carbide (FCC_A1#2) in some Ni-based matrix. Initially I assume spherical particles. When I start the simulation, at the interfaces at 0°, 90°, ... of the sphere, actually a driving force for dissolution ...
- Wed Mar 02, 2016 4:21 pm
- Forum: solid-solid phase transformations
- Topic: Incipient melting of NbC in a nickel-matrix
- Replies: 9
- Views: 5612
Re: Incipient melting of NbC in a nickel-matrix
Dear Bernd, using "database global" and leaving away the broken constraint for component 7 in MC is now leading to quite stable calculations. Still some slight instabilities are present at the liquid / MC interface (which is probably not so critical for our application). They are connected to spots ...
- Tue Mar 01, 2016 3:25 pm
- Forum: solid-solid phase transformations
- Topic: Incipient melting of NbC in a nickel-matrix
- Replies: 9
- Views: 5612
Re: Incipient melting of NbC in a nickel-matrix
Dear Bernd, thank you for your suggestions. In fact, your values significantly improved the stability of the simulation. Also excluding the jumping of MICRESS into the FCC_A1#1 composition set was important. In principle, now even simulations in the system Ni-Al-C-Co-Cr-Fe-Mo-Nb-Ti run. I am now usi...
- Thu Feb 25, 2016 9:16 am
- Forum: solid-solid phase transformations
- Topic: Incipient melting of NbC in a nickel-matrix
- Replies: 9
- Views: 5612
Incipient melting of NbC in a nickel-matrix
Dear all, I am currently trying to model the incipient melting of niobium carbide particles in a nickel-matrix. I am using simply a cubical particle for test purposes. In principle, liquid phase is formed at the interface between both phases – as expected. But I am getting numerical instabilities, w...
- Wed Oct 01, 2014 10:37 am
- Forum: solid-solid phase transformations
- Topic: Effect of "Number of steps to adjust profiles of initially"
- Replies: 3
- Views: 3564
Re: Effect of "Number of steps to adjust profiles of initial
Dear Bernd, in fact this is no critical issue for us. As long as I am not allowing for nucleation of new gamma prime phase within the matrix, the microstructure is stabilized very easily by MICRESS in the first steps. This probably happens because we anyway limit the phase boundary mobility at lower...
- Tue Sep 30, 2014 10:20 am
- Forum: solid-solid phase transformations
- Topic: Effect of "Number of steps to adjust profiles of initially"
- Replies: 3
- Views: 3564
Effect of "Number of steps to adjust profiles of initially"
Hello, I am wondering about the effect of the setting of "# Number of steps to adjust profiles of initially sharp interfaces?". We are using initially measured composition fields. It is the microstructure of a superalloy containing gamma matrix and eutectic gamma prime phase. These eutectic regions ...
- Tue Apr 01, 2014 1:53 pm
- Forum: tips and tricks
- Topic: abort criterion
- Replies: 1
- Views: 6007
abort criterion
Dear Bernd, we would like to perform MICRESS-calculations in rapid succession (directly operated by a MATLAB-script). To ensure a fast and stable process we are looking for an abort criterion in order to stop and to skip calculations which display numerical problems. Is there any possibility to defi...
- Wed Jan 15, 2014 12:19 pm
- Forum: solid-solid phase transformations
- Topic: Ni-Al precipitation simulations
- Replies: 5
- Views: 5035
Re: Ni-Al precipitation simulations
Hello Bernd, in fact it seems to be the best solution to use a temperature dependent mobility, then the test simulation runs stable as it should. Our goal is to suppress secondary gamma prime phase precipitation below its gamma prime solvus temperature. This would occur because our input concentrati...
- Tue Jan 14, 2014 3:11 pm
- Forum: solid-solid phase transformations
- Topic: Ni-Al precipitation simulations
- Replies: 5
- Views: 5035
Re: Ni-Al precipitation simulations
Hi Bernd, your hints were useful, thank you! When I go on, I would like to be able to simulate the same setup (i.e. a given concentration field) heating it up from very low temperatures. This is for studying the behaviour during the beginning of a heat treatment. However, if a phase interaction betw...