MICRESS Forum

Hej,

I am performing a solidification simulation similar to CMSX4 but for Alloy 718. The minimum Nb content in the gamma dendrite core in the simulation is less than the value observed in the experiments. The minimum value will observe at the initial seed position.

Is there a possibility in MICRESS to adjust some parameters so that the minimum value that you observed in the dendrite core can be increased?

BR
Chamara

Hej,

There is no way of changing the segregation behavior of Nb, because this would require to change the thermodynamic data. However, I can imagine 3 effects which perhaps could explain the difference between experiment and simulation:

1.) In the 2D cross-section model, initial undercooling is a not well defined parameter which however could influence the segregation behavior. In a 3D simulation, dendrite tip undercooling would be at least 10-15K which could make a difference. However, probably, this effect is not big enough to explain your differences..
2.) In a 2D simulation, you always display the cutting plane which goes directly through the center of the dendrite. In a 3D simulation, as well as in experiments, the probability to hit the center is low, so that you might not see the regions with lowest Nb content.
3.) In SLM, you always have some homogenization due to passage of multiple laser scans. This could have already altered your segregation profiles.

Bernd

Many thanks Bernd for the input.

You pointed out some important points that didn't came to my mind