Abstract: The metal additive manufacturing paradigm assumes that metal components are obtained through various additive techniques using metal as the direct raw material. There are a number of issues with current methods including porosity, variable and potentially unpredictable materials properties, and limitations to use existing alloy powders, and time consuming processes which are limited in their scalability. Additionally, processes using additive manufacturing to obtain molds in conjunction with casting are in use but are costly, time consuming, and result in poor dimensional accuracy (0.020”/inch are typical).
Research is being conducted in an alternative method that uses metal casting as a post processing technique. Additive manufacturing is used to construct a polylactic acid (PLA) form whose surface is a replica of the final desired component with minimal infill. This is then used as a consumable pattern through evaporative casting in a process similar to lost foam casting. Examples produced and process details will be reviewed.
Authors: Sarah Jordan and Mark DeBruin
Keywords: 3-D, 3D, Printing, Additive, Manufacturing, Ductile, Iron, Evaporative, Casting, Fused, Filament, Fabrication, Lost, Foam, Foundry, Gray, Grey, Investment, Manufacturing, Metal, Consumable, Pattern, Patternless, PLA, Polylactic, Acid, SLS, SLM, Steel, Tolerances