Zhihan Hu is currently a PhD candidate in the Department of Nuclear Engineering at Texas A&M University. He obtained a BS in Physics from the University of Science and Technology in China in 2019. He joined Texas A&M University in 2019 as a PhD student. His research interest is nuclear materials degradation under extreme conditions. He has published 14 journal publications, with an h-index of 4.
This study explored solid-state additive friction stir deposition (AFSD) as a modular manufacturing technology, with the aim of enabling a more rapid and streamlined on-site fabrication process for large meter-scale nuclear structural components with fully dense parts. Austenitic 316 stainless steel (SS) is an excellent candidate to demonstrate AFSD, as it is a commonly-used structural material for nuclear applications. The microstructural evolution and concomitant changes in mechanical properties after 5 MeV Fe++ ion irradiation were studied comprehensively via transmission electron microscopy and nanoindentation. AFSD-processed 316 SS led to a fine-grained and ultrafine-grained microstructure that resulted in a simultaneous increase in strength, ductility, toughness, irradiation resistance, and corrosion resistance. The AFSD samples did not exhibit voids even at 100 dpa dose at 600 °C. The enhanced radiation tolerance as compared to conventional SS was reasoned to be due to the high density of grain boundaries that act as irradiation-induced defect sinks.
