Pearlite dissolution
Posted: Fri Mar 12, 2021 3:19 pm
Dear Bernd,
I've been trying to simulate austenite growth in pearlite. I've been trying to match my simulations with what I've observed experimentally. The best fit was obtained with the simulation attached (cb-200Cs-19). As you can see I have two types of growth: at the colony border and inside of the colonies. I have certain questions:
1. The values of interfacial energy are quite difficult to fit and I am not sure about the effect of this value on the morphology. Since my simulations take a very long time it would be great to have an idea of its effect before modifying it. I've seen a lot of literature with quite different values for interfacial energy which makes it harder to choose a suitable value.
2. In these simulations I see the "flat" growth of austenite between the lamella which is also observed experimentally (see attachment "Experimental observation") and undissolved cementite which is expected. However, in experiments we also see some "finger-shaped" growth of the austenite towards the cementite which I am not able to reproduce. In your opinion would it be possible to have some austenite nuclei behave with the "flat" shape and some others with the "finger" shape?
3. Another issue that I have is that the austenite which nucleates inside of the colony grows only along the ferrite without dissolving the cementite on the sides and growing inside the other ferrite lamella.
4. I've tried changing the mobility of alpha/alpha interface to be equal to gamma/gamma and my simulation (cb-200Cs-21) is running for 2 days and nothing happens besides the nucleation, I would like to understand why this is happening.
I thank you in advance for your support.
Kind regards,
Vitoria.
I've been trying to simulate austenite growth in pearlite. I've been trying to match my simulations with what I've observed experimentally. The best fit was obtained with the simulation attached (cb-200Cs-19). As you can see I have two types of growth: at the colony border and inside of the colonies. I have certain questions:
1. The values of interfacial energy are quite difficult to fit and I am not sure about the effect of this value on the morphology. Since my simulations take a very long time it would be great to have an idea of its effect before modifying it. I've seen a lot of literature with quite different values for interfacial energy which makes it harder to choose a suitable value.
2. In these simulations I see the "flat" growth of austenite between the lamella which is also observed experimentally (see attachment "Experimental observation") and undissolved cementite which is expected. However, in experiments we also see some "finger-shaped" growth of the austenite towards the cementite which I am not able to reproduce. In your opinion would it be possible to have some austenite nuclei behave with the "flat" shape and some others with the "finger" shape?
3. Another issue that I have is that the austenite which nucleates inside of the colony grows only along the ferrite without dissolving the cementite on the sides and growing inside the other ferrite lamella.
4. I've tried changing the mobility of alpha/alpha interface to be equal to gamma/gamma and my simulation (cb-200Cs-21) is running for 2 days and nothing happens besides the nucleation, I would like to understand why this is happening.
I thank you in advance for your support.
Kind regards,
Vitoria.