Importing a Scheil Segregation Profile
You can import a previously calculated Scheil segregation profile into the Diffusion Module (DICTRA). A Scheil calculation is a conservative estimate of the segregation that occurs during solidification and is useful when estimating the necessary time/temperature for a homogenizing heat treatment.
From a practical point of view it is also a simple and fast calculation compared to a more accurate, but computationally more difficult, diffusion simulation.
In order to limit the computational effort, this feature cannot be combined with the fast diffusers option in the Scheil module.
Press F1 in Thermo‑Calc to search the help for more information.
This is available in Graphical Mode using the Homogenization template. Also see Graphical Mode example D_10_Fe _Homogenization_from_Scheil.tcu.
Example exa7
In the following example, taken from the Diffusion Module example collection (see About the Examples in the Thermo‑Calc documentation), the Scheil segregation profile for a ferritic stainless steel (Fe-17Cr-1.4Ni-1Mn) was calculated in the Scheil module in Thermo‑Calc.
The profile was then imported into the DICTRA module and a one hour homogenizing heat treatment at 1200° C was simulated. For the simulation a domain size of 100 μm was assumed, which approximately corresponds to the secondary dendrite arm spacing.
The plots show the initial (left) and final (right) Ni profile.