Thermo-Calc 2024a Available Now
Webinar on Thermo-Calc 2024a Release
New Keyhole Model
A keyhole model has been introduced in the AM Module. In additive manufacturing, when the laser beam intensity is high, which is often done to increase productivity, evaporation of liquid metal creates a recoil pressure that pushes down the liquid to form a cavity, which is called a keyhole. You can see this demonstrated on the right side of the image below.
A representation of the additive manufacturing process comparing the effects of low and high laser beam intensity. High energy (right) creates a recoil pressure that pushes down the liquid to form a cavity, which is called a keyhole.
The Additive Manufacturing Module now includes a model that computes the keyhole shape and corresponding mesh that is used for the steady-state simulation. The model also includes the effect of multiple reflections of the laser beam on the keyhole walls.
From example AM_06b, this Steady-state temperature distribution around the melt pool for SS316L with P = 80 W and scanning speed = 400 mm/s using the calibrated Gaussian heat source with the keyhole model. A keyhole can also be seen formed just below the location of the heat source.
Calibrate Volume Heat Source Parameters Using Experimental Melt Pool Data
A Heat source calibration option has been added to the AM Module in order to improve the ability to predict the melt pool size under various process conditions. This new feature allows users to import experimental melt pool data for a range of processing parameters.
A screenshot from the AM Module in Thermo-Calc showing imported experimental melt pool data for the new Heat source calibration feature.
Users can calibrate the heat source parameters to match the experimental data for your material and processing conditions. Once you have finished the optimization, you can plot the Heat calibration parameters and the Melt pool dimensions as a function of energy density (power/scan speed) and select a function for each heat source parameter.
Heat calibration parameters for a double ellipsoidal calculation.
The Heat source functions can be saved as a user-defined heat source, which will be available from the heat source menu.
Two examples are included in the software demonstrating this new feature:
New Columnar to Equiaxed Transition (CET) Property Model
Another valuable addition for Additive Manufacturing users and for those of you working with casting is the new Columnar to Equiaxed Transition Property Model. This Property Model calculates the fraction of equiaxed grains that correlates with a certain solidification condition, specifically thermal gradient (G) and solidification growth rate (v). This provides valuable information on the solidification microstructure.
Three new examples are included in the release demonstrating this new model:
One of the plot results from example PM_G_15 where the CET curves for a Ni-26Al-9Cr alloy are plotted compared to experimental data. In this example, the nickel demo databases are used, which are available to all users.
New Parallel Coordinates Plot Type
For those working with Materials Design, a new Parallel Coordinates plot type is introduced in the Property Model Calculator.
Screenshot of the new Parallel Coordinates plot type is introduced in the Property Model Calculator.
The Parallel coordinates plot is useful when interpreting multidimensional data and to compare how different parameters affect each other. This is especially useful in materials design after performing a batch or uncertainty set of evaluations when multiple inputs are varied at the same time and multiple model outputs are given as a result.
Interpreting results of the plot:
The new plot type is used with the Property Model Calculator and either the Grid, Batch, or Uncertainty Calculation Type.
New Scheil Property Model
A new Scheil Property Model is available for all users of Thermo-Calc. This new Property Model is essentially the same as the Scheil Calculator already included in the software, but implementing Scheil as a Property Model allows users to benefit from the additional calculation types available in the Property Model Calculator, including multi-axis Grid, Min/Max, Uncertainty, and Batch.
A heat map of the Freezing range from a Scheil calculation for an Al-1Si-1Mn-0.7Mg-0.6Fe-0.1Cu alloy using the new Scheil Property Model with the grid calculation type.
Crack Susceptibility Coefficient Property Model Improved
The Crack Susceptibility Coefficient Property Model received two new models in this release. In addition to the original Clyne and Davies model, you can now select Kou or Easton models.
Screenshot of the settings in the Crack Susceptibility Coefficient Property Model, showing all the models including the new Kou and Easton models.
The Model also received additional Scheil settings. For example, users can now select Scheil with Back Diffusion in Primary Phase or Scheil with Solute Trapping, in addition to Classic Scheil. The Advanced Scheil Options have also been expanded in the Property Model.
Yield Strength Model Improved
The intrinsic strength model has been completely overhauled in order to improve the Yield Strength Model. Previously, intrinsic strength was only calculated per element and only for FCC, BCC, and HCP. Now, the model formulation corresponds to a surface of reference with end-members.
The plot shows how the intrinsic strength of FCC_A1#2 (in this case TiC) is accurately calculated with increasing volume fraction.
This change enables accurate modeling of the strengthening effect to:
New Martensitic Steel Strength Property Model in the Steel Model Library
The Steel Model Library introduces one new Property Model, Martensitic Steel Strength, which calculates the yield strength and/or hardness of martensitic steels.
A new example is included in the release demonstrating this new model:
The plot shows the tempering temperature compared to the total hardness of three tempered AISI steels (1030, 1095 1144) compared to handbook data from Penha, et al. (2013), calculated using the new Martensitic Steel Strength Property Model.
New Strain-Age Cracking Property Model in the Nickel Model Library
The Nickel Model Library also introduces a new Property Model, Strain-Age Cracking, which is used in applications related to welding and additively manufactured components where there are interface strains between γ’ (gamma prime) and the matrix.
Parallel plot of the SAC risk factor along with experimental and calculated solvus of γ’ for the three alloys compared in [2020Zho], calculated using the new Strain-Age Cracking Property Model.
Transform 3D Size Distribution to 2D in the Precipitation Module (TC-PRISMA)
The Precipitation Module (TC-PRISMA) adds the ability to convert three-dimensional (3D) distribution to two-dimensional (2D) distribution, which allows users to compare simulations with experimental data.
Users can calculate two-dimensional:
This figure illustrates the two-dimensional cross section obtained from sectioning a three-dimensional dispersion of spheres, relevant to Scanning Electron and Optical micrographs taken of material with second phase precipitates.
To learn more, you can read the release notes or the help, which both go into detail about this new feature.
A new example is included in the release demonstrating this new feature:
Databases and Thermophysical Properties
New Databases
TCSALT1: Molten Salts Database
TCSALT1 is a completely new thermodynamic database for molten salts. The database can be used for a variety of applications, especially for processes involved with recycling aluminum where fluxes are used. The database covers the most common fluxes and you can study the flux ability to dissolve inclusions, like oxides, removal of unwanted elements in the Al-melt and how this varies with flux composition and temperature.
The database can also be used to understand High Temperature Corrosion where molten salts can destroy the corrosion resistance.
The database includes:
Updated Databases
TCCU6.2: Copper-based Alloys Database
The copper-based alloys database was updated to version TCCU6.2. Users who have a license for TCCU6 and a valid Maintenance and Support Subscription receive this upgrade for free.