Microstructural engineering of additive manufactured metals

With MicroAM, we will introduce microstructural engineering into the field of additive manufacturing (AM) of metals. This will (i) set the stage for optimizing metals microstructures in-situ during the AM process, as well as ex-situ during post-AM treatments, and (ii) enable predictions of the microstructural evolution, and thus the changes in properties, while AM components are in use.
AM is at present revolutionizing metal manufacturing, but the huge potential of microstructural engineering, used for decades in conventional manufacturing, has not been systematically explored for AM. Voids are hard to avoid, and local stresses are always present. An additional main task of MicroAM is thus to incorporate the individual and combined effects of voids and local stress into microstructural engineering—this represents a major fundamental challenge and has never been done before, but opens new design opportunities.
MicroAM will introduce the following novel, key elements, which I foresee to be essential to the future of metal AM:
• A laboratory-based X-ray microscope capable of mapping local residual stress non-destructively in 3D with a spatial and strain resolution better than 5 μm and 5×10−4, respectively.
• A multi-scale AM process–microstructure–property–performance simulation platform that includes models for simulations of the microstructural dynamics for all of the following stages: (i) during the AM process, (ii) while exposed to post-AM stimuli (as selected for microstructural engineering), and (iii) when loaded during in-service operation.
• A theoretical framework that includes the effects of multi-scale voids and local residual stresses in microstructural engineering, and that addresses the local microstructural evolution during exposure to mechanical, thermal and corrosive stimuli/loads, thus laying the foundation for design of AM-defect tolerant microstructures.
• An exploitation of the microstructural engineering potential for AM of metals by two demonstration cases.
It is my dream to use this opportunity to demonstrate how my knowledge acquired during a long career within advanced 2D, 3D and 4D characterization and modelling of conventionally manufactured metals can be transferred and applied to the new and rapidly growing AM field, and that I may thereby contribute to metals research and development for the future.