Development and characterisation of ultrafine hierarchically structured eutectic Ti-Fe-based alloys using additive manufacturing and advanced tomographic techniques

ongoing

UTIFE aims at further developing ultrafine eutectic Ti-Fe-based alloys to increase their maturity using selective laser melting (SLM) additive manufacturing. The project will characterize the alloys by using advanced tomographic techniques to determine their composition-processing-microstructure-property relationships, increasing the understanding of the eutectic Ti-Fe alloy system and the effects of processing parameters during SLM on eutectic alloys as a whole. The objectives of the project are to i) explore material SLM processing parameters to obtain crack-free samples with a high material density, ii) study and understand the mechanisms of crack formation, porosity generation and/or healing during the printing process, and iii) provide a multiscale (nano to micro) 3D characterization of the material microstructure. These objectives will be met using the state-of-the-art laser powder bed fusion (LPBF) to process the eutectic alloys and determine the effects of processing parameters on the as-printed material. The material will also be printed using a state-of-the-art in-situ synchrotron Xray computed tomography (S-XCT) SLM replicator to characterize the effects of printing parameters on defect generation and microstructural evolution during printing. A full characterization using traditional and advanced characterization techniques in 2D (SEM-EBSD, TEM, XRD) and 3D (3D FIB-SEM-EBSD, TEM, XCT, S-XCT) will provide critical information about the composition-processing-microstructure relationships in the eutectic Ti-Fe alloys. This project will introduce new hierarchically-structured eutectic Ti-Fe-based alloys of high interest for industry and contribute to significant scientific insights between additive manufacturing processing parameters, eutectic microstructures, and material properties in the Ti-Fe alloy system. The insight from this project can help explore other eutectic alloy systems for the development of novel additive manufacturing materials.