Rijul Chauhan

Profile Information
Name
Dr Rijul Chauhan
Institution
Pacific Northwest National Laboratory
Position
Linus Pauling Postdoctoral Fellow
Affiliation
Pacific Northwest National Laboratory
h-Index
3
ORCID
0000-0002-7963-764X
Biography
Rijul Chauhan is a Linus Pauling Distinguished Postdoctoral Fellow at Pacific Northwest National Laboratory (PNNL). He earned his Ph.D. in Nuclear Engineering from Texas A&M University in 2025, following dual bachelor's degrees in Nuclear Engineering and Physics from Idaho State University in 2019. His research expertise spans ion irradiation, stress–irradiation interactions, thermal characterization of nuclear materials, finite element analysis, molecular dynamics, ab initio modeling and scanning electron microscopy techniques.
Expertise
Accident Tolerant Fuel, Corrosion, Finite Element Analysis, Fuel Cladding, Ion Radiation, Molecular Dynamics, Neutron Radiation, Nuclear Fuel, Steels, Swelling
Publications:
"Abnormal grain growth driven by high-temperature proton irradiation in nanocrystalline Ni" Kelvin Xie, Kenneth Cooper, Yu Lu, Rijul Chauhan, Jana Howard, Yaqiao Wu, Lin Shao, Michael Demkowicz, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms Vol. 572 2026 166009 Link
In this study, we examine a nanocrystalline Ni thin film exposed to high-temperature proton irradiation and compare it with as-deposited and annealed-only counterparts. Despite lacking thermal spikes typical of heavy ions, 400 °C proton irradiation drives pronounced grain growth in select grains, whereas annealing alone yields only modest coarsening. Grain-boundary statistics show fewer low-angle boundaries (10–20°) and more high-angle boundaries (55–60°), consistent with irradiation-enhanced mobility of high-misorientation boundaries. The irradiated films retain a random texture, with no evidence of texture development or sharpening. Mechanisms, such as radiation-enhanced grain boundary diffusion, beam-induced heating, and ion channeling-mediated selective grain growth, are unlikely to be the predominant drivers to explain the resultant microstructure. Instead, we suggest irradiation-induced modifications of grain-boundary structure, including possible complexion transitions, as one plausible explanation for this selective grain growth and retention of random texture. However, additional temperature–dose studies are required to confirm the mechanism.