IMMC
![]() Post-doctoral researcher Dr. at UCL in 2022 Contact - Personnal web page Main project: Multi-material 3d additive manufacturing Funding: Researcher Supervisor(s): Pascal Jacques High entropy alloys (HEAs) are a new family of metallic alloys. In contrast to conventional alloys, HEAs have multiple principal elements e.g. the equiatomic "Cantor" alloy CrMnFeCoNi. Alloys in this range of chemical composition have gathered attention only recently. From what was observed in conventional alloys, it was expected that HEAs microstructure be composed of several intermetallic phases but some systems are surprisingly single phase solid solution. Moreover, such single-phase alloys have excellent mechanical properties. For instance, CrMnFeCoNi possess a large fracture toughness, which increases with decreasing temperature, putting this alloy on par with the current best alloys used for cryogenic applications. As such, the objective of the thesis is to understand the underlying mechanisms responsible for the observed macroscopic behavior of such alloys. The thesis aims to answer several questions such as: What are the mechanisms responsible for the increase in ductility, strength, and fracture toughness with decreasing temperature? What high-throughput methodology would be able to screen the vast range of possible chemical composition of HEAs for high performance alloys? To understand the deformation mechanisms, several HEAs will be fully characterized from casting to mechanical testing. For the fracture toughness measurements, the essential work of fracture method will be employed as it is best suited for ductile thin sheets than compact tests. Diffusion multiples will be explored as a possible high-throughput method, as the presence of composition gradients allows the simultaneous characterization of a range of composition by techniques such as EDX, EBSD and nano-indentation. IMMC main research direction(s): Processing and characterisation of materials Keywords: calphad fracture mechanics metallic alloys metallurgy Research group(s): IMAP ![]() Recent publicationsJournal Articles1. Gerdt, L.; Müller, M.; Heidowitzsch, M.; Kaspar, J.; Lopez, E.; Zimmermann, M.; Leyens, C.; Hilhorst, Antoine; Jacques, Pascal. Alloy Design of Feedstock Material for Additive Manufacturing—Exploring the Al-Co-Cr-Fe-Ni-Ti Compositionally Complex Alloys. In: International Thermal Spray Conference : Thermal Spray 2023: Proceedings from the International Thermal Spray Conference, Vol. 2023, p. 414-421 (2023). doi:10.31399/asm.cp.itsc2023p0414. http://hdl.handle.net/2078.1/275076 2. Chen, Wei; Hilhorst, Antoine; Bokas, Georgios; Gorsse, Stéphane; Jacques, Pascal; Hautier, Geoffroy. A map of single-phase high-entropy alloys. In: Nature Communications, Vol. 14, no.1, p. 2856 (2023). doi:10.1038/s41467-023-38423-7. http://hdl.handle.net/2078.1/275007 3. Ding, Lipeng; Hilhorst, Antoine; Idrissi, Hosni; Jacques, Pascal. Potential TRIP/TWIP coupled effects in equiatomic CrCoNi medium-entropy alloy. In: Acta Materialia, Vol. 234, p. 118049 (2022). doi:10.1016/j.actamat.2022.118049. http://hdl.handle.net/2078.1/261142 4. Hilhorst, Antoine; Pardoen, Thomas; Jacques, Pascal. Optimisation of the essential work of fracture method for characterization of the fracture resistance of metallic sheets. In: Engineering Fracture Mechanics, Vol. 268, p. 108442 (2022). doi:10.1016/j.engfracmech.2022.108442. http://hdl.handle.net/2078.1/260090 5. Hilhorst, Antoine; Leclerc, Julien; Pardoen, Thomas; Jacques, Pascal J.; Noels, Ludovic; Nguyen, Van-Dung. Ductile fracture of high entropy alloys: From the design of an experimental campaign to the development of a micromechanics-based modeling framework. In: Engineering Fracture Mechanics, Vol. 275, p. 108844 (2022). doi:10.1016/j.engfracmech.2022.108844. http://hdl.handle.net/2078.1/265590 6. Zuo, X.; Miotti Bettanini, Alvise; Hilhorst, Antoine; Jacques, Pascal; Moelans, N. Influence of 5 at.%Al-Additions on the FCC to BCC Phase Transformation in CrFeNi Concentrated Alloys. In: Journal of Phase Equilibria and Diffusion, Vol. 42, p. 794-813 (2021). doi:10.1007/s11669-021-00924-7. http://hdl.handle.net/2078.1/251421 7. Hilhorst, Antoine; Jacques, Pascal. Diffusion Multiples as a Tool to Efficiently Explore the Composition Space of High Entropy Alloys. In: Journal of Phase Equilibria and Diffusion, Vol. online (2021). doi:10.1007/s11669-021-00902-z. http://hdl.handle.net/2078.1/250263 8. Bokas, Georgios; Chen, Wei; Hilhorst, Antoine; Jacques, Pascal; Gorsse, S.; Hautier, Geoffroy. Unveiling the thermodynamic driving forces for high entropy alloys formation through big data ab initio analysis. In: Scripta Materialia, Vol. 202, p. 114000 (2021). doi:10.1016/j.scriptamat.2021.114000. http://hdl.handle.net/2078.1/246724 Conference Papers1. Gerdt, L; Müller, M; Heidowitzsch, M; Kaspar, J; Lopez, E; Zimmermann, M; Leyens, C; Hilhorst, Antoine; Jacques, Pascal. Alloy design of feedstock material for additive manufacturing: exploring the Al-Co-Cr-Fe-Ni-Ti compositionally complex alloys. In: Thermal Spray Proceedings. Vol. ITSC 2023 , p. 414-421 (2023). 2023 xxx. doi:10.31399/asm.cp.itsc2023p0414. http://hdl.handle.net/2078.1/275077 2. Hilhorst, Antoine. Développement d’alliages à haute entropie pour fabrication additive combinant méthode expérimentale et approche CALPHAD. 2022 xxx. http://hdl.handle.net/2078.1/270242 3. Hilhorst, Antoine. Statistical aspects of the essential work of fracture method. 2022 xxx. http://hdl.handle.net/2078.1/270241 4. Hilhorst, Antoine. Combined computational and experimental alloy design of High Entropy Alloys (processed by AM). 2022 xxx. http://hdl.handle.net/2078.1/270239 5. Hilhorst, Antoine; Bille, Pierre; Favache, Audrey; Jacques, Pascal. High-throughput Experimental Design of High-Entropy Alloys. 2019 xxx. http://hdl.handle.net/2078.1/216294 6. Nguyen, Van-Dung; Harik, P; Hilhorst, Antoine; Pardoen, Thomas; Jacques, Pascal; Noels, Ludovic. A multi-mechanism non-local porosity model for high-ductile materials; application to high entropy alloys. In: Book of abstracts (online) APCOM2019, 2019, MS501A - # 0155 xxx. http://hdl.handle.net/2078.1/226263 7. Hilhorst, Antoine; Pardoen, Thomas; Jacques, Pascal. Sur la caractérisation de la ténacité exceptionnelle des alliages à haute entropie à base de métaux de transition. 2019 xxx. http://hdl.handle.net/2078.1/226233 8. Hilhorst, Antoine; Pardoen, Thomas; Jacques, Pascal. On the Characterization of the Exceptional Fracture Toughness of CrMnFeCoNi High Entropy Alloy. 2019 xxx. http://hdl.handle.net/2078.1/216292 9. Hilhorst, Antoine. High-Troughtput characterization method of non-equiatomic high entropy alloys. 2018 xxx. http://hdl.handle.net/2078.1/202927 Dissertations1. Hilhorst, Antoine. Critical assessment of the plasticity and fracture properties of high entropy alloys compared to conventional alloys, prom. : Jacques, Pascal ; Pardoen, Thomas, 31/05/2022. http://hdl.handle.net/2078.1/264050 |