Aug, 2026
ORNL Report
Publications
Showing 70 results for Author: Yousub Lee
Aug, 2026
ORNL Report
Residual Stress Development and Deformation of Wire-Arc Direct Energy Deposition Parts
Mar, 2026
Journal
An Integrated Computational Materials Engineering (ICME) Approach to Design Nonlinear Transition Zones Between Dissimilar Metals
Current approaches to designing graded transition joints (GTJs) between dissimilar metals often rely on linear changes in both composition profiles and thickness of each sublayer. This increases fabrication cost and may not be optimal with respect to residual stress or the formation of undesirable phases. In this study, GTJs between P91 ferritic/martensitic steel and 347H…
Mar, 2026
Conference Paper
Micromechanical Surrogate Machine Learning Model for Creep Deformation Modeling
Process variability during the manufacture of gas turbine engine hot section components can significantly affect the material’s resulting microstructure. In casting, for instance, geometric variation within a component (thin sections versus thick sections, radial location) influences cooling rates and the resulting grain size. The high temperature creep response is known t…
Mar, 2026
Journal
Residual strain and microstructure evolution in 316L stainless steel fabricated by hybrid additive/subtractive manufacturing
The extreme thermal gradients in additive manufacturing (AM) result in residual strains. Subsequent machining operations can relieve the AM strains but can introduce additional strains. AM and machining on the same platform, also called interleaving, during hybrid manufacturing has been shown to improve productivity. However, the impacts of these operations on the resultin…
Mar, 2026
Journal
Spatially resolved phase transformation mapping in 410 Stainless Steel During Additive Manufacturing Visualized via Real-Time Infrared Data
In this study, we demonstrate that spatially resolved cooling curves derived from real-time infrared (IR) thermography during additive manufacturing (AM) can capture spatial variations in phase transformation temperatures through cooling curve analysis (CCA). Using this approach, we show that during laser hot-wire deposition of 410 stainless steel (410SS), the martensite s…
Feb, 2026
Book Chapter
Modeling and Simulation of LFAM: Polymers, Metals, and Cements and Clays, a Review
Large-format additive manufacturing (LFAM) is considered to be one of the most efficient systems for producing large-sized parts. This is primarily due to the high deposition rate, minimal material waste, and cost-effectiveness in terms of both materials and processes. However, the development of modeling and simulations are not maintaining pace with the rapid advancement…
Feb, 2026
Journal
Role of Computational Parameters on Predicting Self-Consistent Residual Stress and Distortion during Wire Arc Additive Manufacturing
Production of three-dimensional metallic parts through integration of an articulated robot and gas metal arc welding, also known as wire arc additive manufacturing (WAAM), can produce large-scale components with moderate geometrical complexity. This technology is particularly appealing due to its high deposition rates, scalability, and cost-effective feedstock compared to…
Jan, 2026
Journal
A critical review on additive manufacturing of refractory alloys from a data analytics perspective- beyond nickel-based superalloys
Refractory alloys (RAs) are promising materials due to their exceptional physicochemical properties, but most research remains at the laboratory scale. For broader adoption, advancements in manufacturing are essential. Because their high stability makes conventional methods like machining and casting difficult, additive manufacturing (AM) is emerging as an effective approa…
Jan, 2026
Journal
Extended Continuous Cooling Transformation Diagram for 410 Stainless Steel encompassing δ→γ and γ→α′ Transformations Determined by Dilatometry
In this study, we use dilatometry to construct an extended Continuous Cooling Transformation (CCT) diagram for 410 stainless steel, capturing both δ→γ and γ→α′ transformations specifically for directed energy deposition (DED) additive manufacturing (AM) applications. To ensure that the findings are representative of AM specific microstructures and compositions, dilatometry…
Dec, 2025
Journal
Simulation Driven Adaptive Sampling for Neutron-Diffraction Based Strain Mapping of Additively Manufactured Parts
Neutron diffraction based strain mapping is a useful technique for measuring residual strains in additively manufactured (AM) metal parts. The measurement is traditionally done by scanning the sample in a point-wise raster pattern to extract the strain at each position. Since the overall scan can span several hours, adaptive sampling approaches using Bayesian optimization…