Aug, 2026
ORNL Report
Publications
Showing 25 results for Author: Soumya Nag
Jul, 2026
ORNL Report
Influence of Powder Characteristics and Processing Methods on Creep Performance of Powder Metallurgy Hot Isostatic Pressed SS316
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…
May, 2026
Journal
Effect of 316 stainless steel powder processing conditions on microstructure
One parameter that has both economic and performance effects in the manufacturing of steel parts is the powder feedstock used. 316 L steel powder can be produced through water atomization or gas atomization, where both the powder size and the atomization process determine the cost of powder feedstock. Gas atomized powder is spherical and has a lower oxygen content than wat…
Apr, 2026
ORNL Report
POWDER METALLURGY HOT ISOSTATIC PRESSING – WORKSHOP REPORT
Final PM-HIP Workshop report, which has been approved by DOE and attached here for public release through OSTI.
Apr, 2026
Journal
A fast and robust computational modeling approach for density and shape predictions in powder metallurgy hot isostatic pressing
Powder metallurgy hot isostatic pressing (PM-HIP) is an advanced manufacturing process that produces near-net-shape parts with high material utilization and uniform microstructures. PM-HIP is frequently used for producing small-scale parts with complicated geometries and is potentially economical for producing large-scale parts. However, excessive post-HIP shape distortion…
Mar, 2026
Conference Paper
A comparison of plastic and visco-plastic constitutive models for accurate predictions in PM-HIP
Powder metallurgy hot isostatic pressing (PM-HIP) is an advanced manufacturing process that can efficiently produce near net shape parts with high material utilization and uniform microstructures. While the PM-HIP process is used frequently to produce small-scale components, its application to large-scale components is still limited due to inadequate understanding of its c…
Dec, 2025
Journal
New insights on the effects of chemistry and temperature on α’ precipitation during aging of FeCrAl alloys
The effect of Al on α’ precipitation in FeCrAl alloys was studied through thermal aging of several model binary FeCr and FeCrAl alloys with Cr content of 13 wt.%, 17 wt.%, and 25 wt.% with and without 5.5 wt.% Al. Aging was performed up to 1,000 h at varying temperatures from 400 to 500 °C. At 400 °C no age hardening was observed due to slow kinetics at this temperature. F…
Oct, 2025
Journal
Multi-Physics Melt Pool Modeling and Process Optimization for Laser Direct Energy Deposition of Nb-Based Refractory C103: Defect Formation, Geometric Precision, and Process Mapping
Recent developments in additive manufacturing (AM) technology have reignited interest in the fabrication of the Nb-based refractory C103 alloy offering solutions to the challenges posed by traditional manufacturing methods. However, the limited numerical and experimental studies on laser direct energy deposition (DED) of C103 have hindered the understanding of the relation…
Aug, 2025
ORNL Report
Feature Based Qualification of 17-4PH Stainless Steel to Evaluate Location-Specific Variability in Wire Arc Additive Manufacturing
Qualifying large-scale metal additive manufacturing (M-AM) technologies such as wire arc additive manufacturing (WAAM) can be challenging. This is especially significant in precipitation hardened martensitic stainless steels like SS 17-4PH, where thermal histories induce location-specific microstructural variability and property anisotropy. The Department of Defense (DOD)…
Aug, 2025
Journal
A visco-plastic constitutive model for accurate densification and shape predictions in powder metallurgy hot isostatic pressing
Powder metallurgy hot isostatic pressing (PM-HIP) is an advanced manufacturing process that produces near net shape parts with high material utilization and uniform microstructures. Despite being used frequently to produce small-scale components, the application of PM-HIP to large-scale components is limited due to inadequate understanding of its complex mechanisms that ca…