Showing 134 results for Author: Sebastien N. Dryepondt
Sep, 2026
Journal
High temperature cast HK30Nb (Fe-25Cr-20Ni-1.4Nb-0.2C) alloy was fabricated by laser powder bed fusion (LPBF) and creep tested in the as-printed condition between 700 and 800°C. Significant microstructure evolution took place during long-term testing at 700 and 800°C, with the formation of coarse Cr-rich carbides, sigma phase precipitates and creep cavities at grain bounda…
Sep, 2026
Journal
We investigated the high-temperature behavior of binary eutectic nickel-base alloys with low-solubility elements, towards developing alloys with new combinations of structural and functional (e.g. thermal or corrosion) properties. Based on thermodynamic screening, we cast binary near-eutectic Ni-B, Ni-Ca, Ni-Ce, Ni-La, Ni-Y, and Ni-Zr alloys and characterized their microst…
Aug, 2026
Journal
Solidification cracking remains a persistent barrier to laser powder bed fusion (LPBF) processing of solid-solution-strengthened (SSS) Ni-based superalloys and is commonly attributed to carbide formation, liquation-type failure, or elemental segregation. In this work, the cracking behavior of three SSS Ni-based superalloys—Inconel 625 (625), Inconel 617 (617), and Haynes 2…
Aug, 2026
ORNL Report
The advanced materials and manufacturing technologies (AMMT) program is investigating two Ni-based alloys of interest to the nuclear industry, alloy 625, due to its acceptable high temperature properties and availability in various forms, and Haynes 244, a promising low Cr high strength alloys for molten salt applications. These two alloys were fabricated by laser powder b…
Jul, 2026
ORNL Report
The U.S. nuclear energy expansion goals are driving the demand for manufacturing routes that can rapidly produce large, complex, near net shape components. Powder metallurgy hot isostatic pressing (PM HIP) is an advanced manufacturing technique that can be economically scaled-up, while alleviating the supply chain challenges that forging and casting face in terms of cost a…
Apr, 2026
ORNL Report
Mar, 2026
Conference Paper
Gas turbine efficiency is typically limited by the maximum allowable temperature for components at the inlet side and in the hot gas flow. Refractory alloys and SiC/SiC ceramic-matrix composites (CMCs) are promising candidates for advancing operating temperatures beyond those of Ni-based alloys (>1200 °C). Refractory alloys are more suitable than SiC/SiC CMCs for dynamic c…
Mar, 2026
Conference Paper
The Advanced Materials and Manufacturing Technologies (AMMT) program is aiming at the accelerated incorporation of new materials and manufacturing technologies into nuclear-related systems. Complex Ni-based components fabricated by laser powder bed fusion (LPBF) could enable operating temperatures at T > 700°C in aggressive environments such as molten salts or liquid metal…
Mar, 2026
Conference Paper
Mar, 2026
Conference Paper
PrintCast composites are fabricated by infiltrating a metal mesh or preform (e.g., an additively-manufactured 316L lattices) with molten metal of a lower melting temperature (e.g., A380 aluminum). The resulting PrintCast composite has been shown in the literature to produce diverse and unique mechanical properties that are controllable at the local or global level by adjus…
Mar, 2026
ORNL Report
Under the Advanced Materials and Manufacturing Technologies program, two Ni-based alloys fabricated by laser powder bed fusion (LPBF) at ORNL and laser powder directed energy deposition (LP-DED) at INL have been evaluated: γ′-strengthened Haynes 282 and solution-strengthened Inconel 625. Printing defects were observed in the LPBF 282 alloy fabricated using a Renishaw AM250…