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Jill Lehmann | Dreamstime
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Better Quality Films

June 25, 2007
Top New Functions in Simulation

Among the utility improvements in SolidCast 7 are simulation parameter settings for reducing the mold/ metal HT coefficient at solidus point (for permanent mold casting), thermal center feeding (for riserless iron casting), and low-pressure simulation.

The objective of casting simulation is to use computer science to design a casting process — before expensive patterns are made, before the patterns are used to form molds, and before the molds are used to shape molten metal, only to find that the castings must be scrapped because of some unforeseen defect in the process. However traditional, that approach requires making changes and producing castings again (and again) until the desired quality is achieved.

Foundries that use simulation can import their customer's 3D models and have the program determine how many risers are required, where they should be placed, what size they should be, and what size and shape to use for sprues, runners, and gates. Then, they simulate and visualize, on a computer screen, the entire process of casting the part, including pouring, solidification, and shrinkage formation.

Using this information, a foundry can fine-tune its design to produce the best casting possible, at the lowest cost. Using optimization software, the system may even redesign the process. Because simulation is based on software, new features and techniques can be implemented with that software as soon as they are developed.

One of the recent advances in the SolidCast simulation software package is the ability to produce better movies simulating metal flowing into a mold cavity. These higher-quality movies produced by SolidCast's new Version 7 are created in the widely used WMV format.

Finite Solutions Inc. (www.finitesolutions.com), publisher of the SolidCast products, claims that the latest movie files are in fact quite compact, but the picture quality has been dramatically improved — much clearer and more vivid than was possible to display in prior versions of the software.

At the same time, iso-surface movies have been adjusted so that they are created in the background, like the other movie functions, so that a casting designer can work on other tasks while the movie is being created. David Schmidt of Finite Solutions, recently told FM&T that "the software is under continuous development, and has been for over 20 years."

Among other new features added to SolidCast for Version 7, are:

  • New compatibility — New compiler technology allows Finite Solutions to provide full compatibility with multi-processor, dual-core and Hyperthreading technologies. Previously, these functions had to be disabled on individual machines, to prevent execution errors.
  • Speed improvements — A 20% speed increase in SolidCast simulations, meshing, view factor calculations, and shell creation functions.
  • New and improved utilities — A number of new utilities, as well as several that have been improved or expanded. And, several utilities have been newly documented in the version 7.0 training workbook.

The utility changes are:

  • Data Capture (Temperature) —This utility is used to create a grid of thermocouples that can track temperatures in the casting and mold. It's not a new utility, but it has been completely documented in the training workbook.
  • Early Fill Tilt Pour — This allows the user to specify a point in tilt pouring when most or all metal has filled the mold, prior to completion of the tilt. For example, the system could be set to pour 90% of the metal during the first half (45°) of a 90° tilt pour.
  • Filter Shape — This new function creates a rectangular filter shape with specified open area as a STL file. The STL can be added to a SolidCast model to simulate metal flow through the filter.
  • Iron Property Calculator — Previously, iron casting modulus values of more than 3 cm (1.18 in.) were calculated as though the modulus were 3 cm, due to limitations in the VDG Nomograms. Now, the range of the program has been extended to calculate iron properties for heavier castings. Both property calculations and riser design functions of this utility have been completely documented in the training workbook.
  • Ladle Calculations — In the previous version, fill times longer than100 seconds caused an error to occur in FlowCast. This has been corrected.
  • Mask Material Density in Risers — This utility has been completely documented in the training workbook.
  • Project Viewer — The Project Viewer Utility now displays the number of STL surface facets in a model.
  • Solidification Time Gradient — Calculations of gradients in the casting are based on solidification time, making it possible to predict the likelihood of hot tears in the casting.
  • Simulation Parameters — This feature lets the user adjust some system settings that previously required manipulating files in the SolidCast folder.