Synchrotron X-rays to engineer novel alloys for additive manufacturing

Abstract

Metal-based additive manufacturing (AM), colloquially termed 3D printing, is resulting in a paradigm change across multiple industries such as the aerospace. In particular, the advantages of AM account estimated production savings up to 50% for titanium based components, by missing out exorbitant machining costs and material loss. Nevertheless, the vast majority of the alloys used nowadays for AM are based on compositions inherited from conventional manufacturing. As are result, complex and costly process chains are usually necessary to adapt the materials to the foreseen application. It is therefore essential to create new alloys to exploit the metallurgical conditions of AM and achieve maturity in this technology. High resolution 3D and 4D synchrotron characterization methods are playing a decisive role to unveil the mechanisms governing the microstructure formation in these novel materials. Our contribution will present advances in 4D time-resolved characterization which serve us to discover a transformation which allows breaking up the anisotropy and controlling the grain size in a Ti-alloy developed for ALM. The methodology employed, namely synchrotron tomography and high energy synchrotron X-ray diffraction at the temperatures at which the transformation takes place, opens up new insights to understand the continuous influence phase transformations have on microstructure formation.