Gravity casting is used to make large parts (typically with iron, bronze, brass or aluminum). Most foundry casting processes, including sand casting and permanent molds, can be modeled with FLOW-3D CAST. Though less violent in its filling process than high pressure die casting, quality can be affected by entrainment of air from overly-turbulent filling, by shrinkage-induced defects and more. The movement of the metal front, as well as location of potential defects and the evolution of temperatures, during filling is accurately predicted. After the filling is complete, the solidification of the metal, and its resulting shrinkage, can also be modeled.
Accurate Filling Simulations
Filling in a casting process consists of analyzing the filling pattern and associated defects, for instance, whether defects are sent to a riser or remain trapped in the part. Simulation analysis allows a design to be tested before ever going into production, both validating its effectiveness and saving money. The accuracy of the filling is not only important to track the locations of oxide defects and entrapped air, but it is also key for solidification results. A correct fill pattern means a correct thermal pattern at the end of the fill. This thermal pattern is the basis for a solidification analysis.
Solidification of Castings for Foundry Applications
There are a wide range of defects associated with solidification, including segregation, thermally-induced stresses, and micro and macro porosity. An important first step to obtaining correct solidification analysis is accurate filling. An accurate fill captures the correct thermal profile, which is an initial condition for solidification modeling. FLOW-3D CAST can detect many solidification-related defects enabling foundries to design casting parts more quickly and reduce scrap rate.