Showing 139 results for Author: Peeyush Nandwana
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…
Jul, 2026
Journal
Synergizing wire arc-directed energy deposition (WA-DED) additive manufacturing (AM) with particle-strengthened creep strength-enhanced ferritic (CSEF) steels enables fabrication and repair of critical power-plant components. Investigations focused on fusion-welded particle-strengthened CSEF steels, such as Grade 91 steel, have linked microstructurally heterogeneous region…
Jul, 2026
Journal
Binder Jet Additive Manufacturing (BJAM) is a promising manufacturing pathway to produce H13 steel dies and tooling with complex geometries for applications in high pressure aluminum die casting, hot stamping, and injection molding. While fully dense H13 coupons produced using BJAM have been subjected to detailed microstructure characterization, properties which are critic…
Apr, 2026
Journal
This study investigates the additive manufacturing (AM) processing, microstructural evolution, and resulting mechanical and thermal properties of multi-material components combining 17-4PH stainless steel and pure copper (Cu) fabricated via laser powder directed energy deposition (LP-DED). Conventional tooling steels exhibit limited thermal conductivity, significantly con…
Apr, 2026
ORNL Report
Mar, 2026
Conference Paper
Blown powder directed energy deposition (DED) hybrid machine tools are particularly beneficial when the net shape of a component is to be manufactured in an additive and machined interleaved fashion. This investigation seeks to analyze the effect of the additive head lean angle relative to the part on blown powder DED surface contamination due to overspray. These hybrid DE…
Mar, 2026
Journal
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
Journal
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
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
Journal
Chromium (Cr) alloys combine low density with high-temperature strength but suffer from brittleness and rapid softening. Body-centered orthorhombic (BCO) CrNi2 laths have been shown to improve Cr-alloy high-temperature strength retention, yet their thermal stability and transformation behavior remain unclear. CrNi2 conventionally forms through long-range ordering from a fa…