Enhancements for powder bed fusion (PBF) simulations in the Ansys Mechanical™ application include the following:
Calibration improvements:
Quick Calibration – Cutoff height options: The Quick Calibration feature now offers more flexibility when specifying support cutoff height for the cantilever geometry. Choose a cutoff height between 0 - 8 mm (in 1 mm increments) from the base plate. Previously, the cutoff height was predefined and fixed at 3 to 4 mm.
Quick Calibration – Import CSV file: Save time on setup! You can now directly import a CSV file containing location-specific distortion measurements. This means you can process your setup data in a spreadsheet beforehand for easy import into the calibration wizard.
Full Simulation Calibration – Anisotropic calibration: Anisotropic calibrations are now supported when performing full simulation calibrations.
Electron Beam Melting: You can now simulate an Electron Beam Melting (EBM) process, also known as Electron Beam Powder Bed Fusion (E-PBF). While both E-PBF and L-PBF involve fusing powdered material layer by layer to build parts, they differ significantly in their mechanisms and applications. To accommodate an EBM simulation, the following enhancements have been added to the PBF simulation capability in the Mechanical application:
Build sequence: New Build Sequence options allow you to define distinct heating steps in an EBM process, for different preheats, for example. You can also define location specific process parameters, allowing different portions of the part to have different process parameters for the same layer. The heating method can be temperature or power. Build sequence options are controlled in Build Settings.
Build environment: You can now account for heat losses from radiation, which is the dominant heat transfer mechanism in a vacuum. With radiation effects enabled, a surface boundary condition is applied to the top of a newly laid layer (build step) and the top of the build (cooldown step). Specify an Emissivity value between
0(no radiation) and1(perfect blackbody emitter) to define the surface's ability to emit radiation. Radiation can be specified in the PBF Setup Wizard or in Build Settings.Multiple materials: Simulations are no longer restricted to using a single material for the build (part and supports). You can now model PBF simulations with multiple materials. For a Thermal-Structural AM simulation, the melting temperature for each part geometry must be defined in Engineering Data. A Representative Material option will be displayed in AM Process when multiple material assignments on the part geometries are detected. Choose the material that is most representative of the model as a whole, specifically for thermal properties.
Predefined Support structures can now be assigned a different material than the part geometry they are supporting.
For STL and Generated Supports, the material will be the same as the part they are scoped to.
Modeling of powder (Beta): For voxel meshes, you can generate powder padding around the part and extend the powder below the part to the base plate.
The updates to the underlying AMBUILD Mechanical APDL command made at the last release enable these EBM enhancements in the Mechanical application at this release.
Multi-step heat treatment: The PBF Setup Wizard now supports complex, multi-stage thermal cycles, moving beyond the standard single ramp-and-hold sequence. This allows for high-fidelity simulation of sophisticated industrial heat treatment schedules.
Advanced Cycle Configuration: A new Multiple (Use Table) option enables the definition via a table of intricate cycles with various heating ramps, soak times, and cooling rates.
Granular Solver Control: New Time Stepping controls allow for manual substep adjustments to ensure accuracy during critical thermal transitions.
Automated Workflow: The wizard intelligently detects and preloads existing convection loads into the table, seamlessly transitioning between simple and multi-step configurations.
HPC Platform Services (HPS) for AM simulations: You can now leverage Ansys HPC Platform Services (HPS) to accelerate Additive Manufacturing simulations. Inherent Strain and Thermal-Structural simulations with heat treatment steps can be solved on HPC Platform Services. This feature requires that you set up a Solve Process Queue for the required HPC server details.
UI changes: You'll notice in the UI that items are renamed to be PBF rather than LPBF as a subtle reminder that electron beam simulations are now possible, and not just laser beam simulations. For example, the LPBF Setup Wizard is now the PBF Setup Wizard, the LPBF Hotspot result item is now the PBF Hotspot, and so on.
Additionally, the AM-specific result items are now consolidated under two new buttons in the PBF Process ribbon, as follows:
- Thermal PBF Results
Hotspot
Hotspot Time Correction (Beta)
Heat Flux (Beta)
- Structural PBF Results
Recoater Interference
High Strain
Shrinkline (Beta)
Visualize cutoff direction: An arrow has been added in the graphics window to indicate the direction of base/support cutoff when directional cutoff is chosen (Analysis Settings, Base Removal Type = Directional).
Visualize knockdown factors for voxel mesh (Beta): You can now visualize knockdown factors when using the Voxelizer option in the Cartesian mesh method. The option is available under Display Type > View (Beta) on the AM Process object when the Cartesian Mesh Method has the `Mesh Using Voxelization` set to True or if an STL Support is present in the Tree. This is similar to the capability that is already in place for visualizing knockdown factors for STL Supports.
Visualize conformal mesh (Beta): A new visualization tool is now available for viewing AM simulation results on a conformal body instead of voxel mesh elements. After completing the AM process simulation, select the desired result object under Solution and click Evaluate. Once evaluation is complete, click the Visualize Conformal Mesh (Beta) button on the PBF Process ribbon.
PBF Heat Flux result (Beta): For AM thermal-structural simulations, a new Heat Flux (Beta) result item allows you to evaluate the maximum heat flux for each element at the conclusion of every layer’s deposition step. You can toggle between Total Heat Flux and Directional Heat Flux. Choose between contour plots for gradient visualization or vector plots for flow direction. Visualize data from either the first cooldown step or the last cooldown step.
The Heat Flux (Beta) result can be added to a Thermal AM Analysis System and requires the "Calculate Thermal Flux” output control to be on. If adding the result before the solve, this will be done automatically.
PBF Shrinkline result (Beta): A new shrinkline result allows you to pinpoint areas where one or more layers are contracting more than the surrounding material—this localized contraction is commonly referred to as a shrinkline.