Alloys-By-Design: Application to New Superalloys for Additive Manufacturing

New grades of γ/γ′ nickel-based superalloy for the additive manufacturing process are designed using computational approaches. Account is taken of the need to avoid defect formation via solidification and solid-state cracking. Processing trials are carried out using powder-based selective laser melting, with the heritage alloys IN939 and CM247LC. Microstructural characterisation, calorimetry and hot tensile testing are used to assess the approach employed. The superior processability and mechanical integrity of the new alloys are demonstrated. Suggestions are made for refinements to the modelling approach.