Casting Simulation

Numerical simulation allows the virtual examination of all known casting with dead molds (lost models or duration models), such as sand casting process for producing ingot molds, and permanent molds, such as ingot casting into iron molds. Also, other methods such as (low) pressure casting, continuous casting, gravity casting, centrifugal casting, core blowing, etc. and various special casting methods can find a simulation application.
The simulation projects are carried out in cooperation with our partners using different platforms.

Complex models allow the accurate prediction of important casting properties to predict casting defects. For example, in the fields of

• Solidification (macro and microporosity (including consideration of interdendritic porosities and shrinkages in the light of dissolved gases; Piping; Hot Spots (Insulated solidification) …)
• Residual Stresses (hot crack development; surface cracks, cold cracks, residual stress development; delay; fatigue and mold life …)
• Casting (misruns; air pockets, oxides, surface defects, inclusions, nuclear gases; turbulence; cold welding)
• Metallurgy (Scattered grain; segregation / diffusion, phase transformations …)
• Material Specifications (Mechanical properties; dimensional tolerances …)

Our core competence lies in the optimization of ingot casting process, on the one hand to improve the quality of the ingot, on the other hand to increase the lifetime of the mold. In this area our engineers have been operating successfully for over 10 years.
The correct setting of the process parameters (pre-processing) by inverse modeling is done with extraordinary priority. Only on this basis we can achieve reliable, relevant reality results. We can assist you in obtaining the successful data; if desired, directly at your site.

Data transfer

You can pass us your CAD-data in the following formats:

• STL
• IGES
• STEP
• Optionally we can convert your existing data from any major CAD system or – if necessary – we repair corrupt CAD solid models for the FEM-meshing
• Optionaly we can create the entire CAD model because of your documents (technical drawings, sketches, description, Excel files, etc.)

Material database

• Our standard database includes most of the standard DIN EN ISO or ASTM Fe-based alloys. (Steels and cast iron)
• Furthermore, our databases include all auxiliaries such as sand, casting powder, insulation, bricks etc. Also exothermically reacting substances can be deposited.
• Optionally we offer the determination of the material properties of your special alloys on the basis of chemical analysis by calculation method and / or laboratory tests. By the inverse module a calculation of material and process parameters based on measured temperatures at determining measuring points over time is possible. Primary and secondary cooling can thus be determined very precisely. In this context, we provide you with your required alloy TTT diagrams for the microstructural analysis.
• Optional databases are available for Al- Mg- Ni- Ti- Cu-based alloys

Meshing

• After meshing of the surface a volume mesh based on tetrahedrons is generated. The mesh density can be adapted locally to achieve an optimal balance between computation time and level of detail.
• For the analysis of casting operations, a CAD model of the casting is sufficient. For investment casting method a housing can be created automatically (also in layers).
• Through the layer lattice option the accuracy of the simulation is improved. Depending on the application non-coincident or coincident volume networks can be generated.
• Surface networks and Boolean operations are possible.

Pre-Processing

• A careful pre-processing is the basis for actionable simulations. By your data and the newly measured data on the spot – if necessary – safe parameters can be obtained.
• Materials, boundary- and interaction-relations are defined and adjusted to the complex parameterization of the underlying numerical models.
• Optionally, we support you in your place in the extraction of the necessary data.

Thermal Solver

• The thermal solver allows the calculation of heat flow by taking into account heat conduction, convection and radiation. The heat release associated with phase changes as solidification and solid phase transformations is described by thermodynamic models (enthalpy). The thermal calculation methods provide, among other results on the following areas:
• Hot Spots (isolated solidification), thermal module
• Optimization of the cooling and heating conditions of the form or tool
• Niyama criterion
• Macro- and micro shrinkages
• Volume changes during solidification of cast iron (GJL, GJS, CGI)
• Gating/feeding systems and riser
• Bottlenecks
• Macro- and micro porosity

Flow Solver

• By the exact geometry of the meshed volume model representation of the flow of material can be predicted within the mold. This provides insights into:
• Sand erosion and turbulence
• Misruns and cold welding
• Overflow positioning
• Oxides, air inclusions
• Flow length, air pressure, core gases, colored paths
• Optionally, for various special applications specific models are applied (dead-mold casting, turbulent flows, thixocasting, semi-solid materials, centrifugal casting, core blowing)

Stress Solver

• The stress solver enables fully coupled thermal, fluid and stress simulations with elasto-plastic or elasto-viscoplastic (tough) material properties. Simpler models such as elastic, free or rigid materials can also be combined. This enables the analysis of:
• Thermal and mechanical contact
• Hot cracking, crack propagation, final cracks
• Distorsion
• Fatigue
• Initial and residual stresses of the first type (thermal stresses), the second type (structure induced residual stresses) and third type (molecular level) in casting and mold

Microstructure Solver

• The microstructure formation connected with phase transformations during solidification / cooling of the casting and the mold can be accurately simulated. The model is based on isothermal (TTT) and continuous (CCT) time-temperature-transformation-diagrams.
• Similarly, heat treatment processes and their effects can be simulated on the microstructure.

Post-Processing

• In the powerful post-processing module, the simulation results are tested and visualized on plausibility. All of the calculated values ​​can be displayed visually in the course of time and at any point of the model, or output as a series of values ​​/ graphs.
• Specific indicators show expected imperfections and inhomogeneities in the casting
• Based on the obtained results and shape casting can be optimized to achieve the set goals.
• Optionally, we put for further analysis on custom templates according to your needs and requirements