Superalloy 718 and Derivatives: Poster Session
Program Organizers: Joel Andersson, University West; Chantal Sudbrack, National Energy Technology Laboratory; Eric Ott, GE Additive; Zhongnan Bi, Central Iron and Steel Research Institute
Sunday 8:00 PM
May 14, 2023
Room: Reflections and Waterfront
Location: Sheraton Pittsburgh Hotel at Station Square
Tensile Performance of Direct Energy Deposited IN718 and Oxide Dispersed Strengthened IN718: Kyle Rozman1; Bruce Kang2; Ömer Doğan1; 1National Energy Technology Laboratory; 2West Virginia University
With needs to increase efficiencies, operational temperatures of components must increase. Oxide dispersion strengthening (ODS) has proven useful increasing the operational temperature of steels. Yttria Oxides (Y2O3) particles were mechano-chemical bonded (MCB) to IN718 powder to investigate the ability of IN718 to be strengthened by ODS particles at temperatures above 1000°C. The Y2O3 infused IN718 powder was direct energy deposited using two parameter sets for testing. Additionally, plates of standard IN718 power were built using the same deposition parameters for reference. Specimen blanks were cut from plates and tested as built, with 1080°C and 1200°C homogenization heat treatments. The initial microstructure for all four conditions was dendric with significant Mo, Nb and Ti separation. Homogenization was observed to break up the initial large Mo and Nb precipitates and form Mo, Nb and Ti rich spherical precipitates. Further the 1080°C homogenization heat treatment retained the dendritic structure while the 1200°C was observed to partially recrystallize the grain structure. Minor improvements in the tensile properties were observed at 1050°C by additions of Y2O3. This suggests with further optimization IN718 may be utilized at temperatures above 1000°C with ODS strengthening methods.
Microstructural Studies of Heat-Treated Alloy 625 Fabricated by Laser Powder Bed Fusion: Karen Henry1; 1Naval Nuclear Laboratory
The ability to manufacture complex three-dimensional (3D) components on-demand by additive manufacturing (AM) methods has become increasingly attractive for use in the nuclear industry. The technology also has the potential to raise productivity by delivering parts more rapidly than conventional fabrication methods. To make the most of these benefits, it is necessary to understand process/properties/microstructure relationships.While several commercial studies have demonstrated the ability to fabricate Alloy 625 components by laser-powder bed fusion (L-PBF), these studies have also indicated as-built Alloy 625 is more susceptible to chemical segregation than conventional wrought material. Chemical homogenization of the as-built material can be achieved by heat treatment; however, deleterious phases can form when using heat treatments developed for wrought Alloy 625. This presentation will provide an overview of microstructure and mechanical properties of L-PBF Alloy 625 as a function of annealing temperature from 800 -1200°C (1472 - 2200°F). A range of characterization techniques were used including metallography, scanning electron microscopy, electron backscatter diffraction, and transmission electron microscopy to identify microstructural features associated with optimal and sub-optimal properties. Furthermore, tradeoffs in tensile behavior and Charpy absorbed energy as a result of heat treatment are discussed in relation to the microstructural evolution observed. These studies have been performed to contribute to the current understanding of process/structure/property relationships for Alloy 625 manufactured via L-PBF methods. The fundamental knowledge gained from these studies is key to using AM-fabricated metals for demanding service conditions and/or long lifetimes.
Hot Ductility and Microstructural Evolution of Hastelloy X Produced by Laser Metal Deposition using Powder as Feedstock Material (DED-p): Fabian Hanning1; Daniel Benages Vila1; 1University West
The microstructural evolution of Hastelloy X produced by laser metal deposition using powder as feedstock material has been investigated. A laser power of 1750W together with a scanning speed of 15mm/s and a powder feed rate of 8g/min have been used for deposition based on a DOE using single track depositions. The resulting build microstructure consists of epitaxially grown elongated grains spanning over several deposition layers. Mo-rich precipitates are present on solidification grain boundaries as continuous films. Hot ductility testing shows a narrow brittle temperature range as ductility recovery is rapid in the material, a depressed melting point is however evident as compared to equilibrium solidus of the material. The presence of hot cracks in larger build structures indicates a connection to the hot ductility signature of Hastelloy X and the presence of Mo-rich precipitates on solidification grain boundaries. Phase identification and further microstructural characterization is ongoing to identify the underlying cracking mechanism in DED-p Hastelloy X.
8:00 PM (LBN - P1) Investigation of the Deformation Mechanisms for Bi-Modally Distributed γ’ Precipitates in Allvac 718Plus Superalloy: Geeta Kumari1; Carl Boehlert1; S Sankaran2; M Sundararaman2; 1Michigan State University; 2IIT Madras (See Oral talk for more details)
8:00 PM (LBN - P2) Phase Stability and Phase Transformation Related to Nb/Ta Additions in a Ni-based Superalloy: Chang-Yu Hung1; Stoichko Antonov2; Paul Jablonski2; Martin Detrois2; 1NETL Support Contractor; 2National Energy Technology Laboratory (See Oral talk for more details)
8:00 PM (LBN - P3) Development of Ni Based Superalloys with Medium Entropy Alloys Concept: Elyorjon Jumaev1; Amir Abidov2; Abdullo Khursanov2; 1Almalyk Mining And Metallurgical Combine Jsc; 2Almalyk Mining and Metallurgical Combine JSC (See Oral talk for more details)
8:00 PM (LBN - P4) Laser-Powder Bed Fusion Additive Manufacturing of Haynes 282 Concentrating Solar-Thermal Power (CSP) Plant Parts: Printability, Geometry, Surface, and Microstructure.: Junwon Seo1; Nicholas Lamprinakos1; Anthony Rollett1; 1Carnegie Mellon University (See Oral talk for more details)
8:00 PM (LBN - P5) Phase Evolution and Tensile Deformation of IN718-René41 Graded Superalloy Fabricated by Directed Energy Deposition: Shenyan Huang1; Ke An2; Chen Shen1; Changjie Sun1; Alex Kitt3; 1GE Research; 2Oak Ridge National Lab; 3Edison Welding Institute (See Oral talk for more details)
8:00 PM (LBN - P6) Exploring High Temperature Fretting Wear Behaviour in Wrought and Additively Manufactured DA-718 Superalloy: Sathisha Ch1; Kesavan D2; Sridhar MR1; Arivu Y2; 1GE Rerearch; 2Indian Institute of Technology (See Oral talk for more details)