Zhihan Hu

Profile Information
Name
Dr. Zhihan Hu
Institution
Texas A&M University
Position
Graduate research assistant
Affiliation
Texas A&M University
h-Index
7
ORCID
0000-0002-1535-7489
Biography

Zhihan Hu is currently a postdoc 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, and graduated in 2024. His research interest is nuclear materials degradation under extreme conditions. He has published 25 journal publications, with an h-index of 7.

Expertise
Corrosion, Fuel Cladding, Ion Irradiation, Neutron Irradiation, Nuclear Fuel, Steels, Swelling
Publications:
"Ion irradiation and examination of Additive friction stir deposited 316 stainless steel" Priyanka Agrawal, Ching-Heng Shiau, Aishani Sharma, Zhihan Hu, Megha Dubey, Yu Lu, Lin Shao, Ramprashad Prabhakaran, Yaqiao Wu, Rajiv Mishra, Materials & Design Vol. 238 2024 112730 Link
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.
Additional Publications:
"A parametric study of irradiation-assisted stress corrosion cracking initiation of additively manufactured 316 L stainless steel by using microstructurally-graded specimen" Jingfan Yang, John Snitzer, Zhihan Hu, Lin Shao, Xiaoyuan Lou, Evan McDermott, [2025] Journal of Nuclear Materials · DOI: 10.1016/j.jnucmat.2025.156088
"Origin of sub-surface swelling peaks in ion irradiation and their mitigation through dose rate control" Zhihan Hu, Aaron French, Yongchang Li, Yinyin Hong, Frank A. Garner, Lin Shao, [2025] Materials Today Communications · DOI: 10.1016/j.mtcomm.2025.113553
"Micro-pillar compression of proton-irradiated chromium examined using cross-sectional site selection, electron microscopy, and molecular dynamics simulation" Yongchang Li, Zhihan Hu, Kenneth Cooper, Laura Hawkins, Di Chen, Frank A. Garner, Lin Shao, Miguel Pena, [2024] Journal of Nuclear Materials · DOI: 10.1016/j.jnucmat.2024.155299
"Void swelling in pure iron after sequential self-ion-irradiation at different energies: Effect of injected interstitials and additional damage in regions containing pre-existing voids" Frank A. Garner, Zhihan Hu, Lin Shao, Yongchang Li, [2024] Journal of Nuclear Materials · DOI: 10.1016/j.jnucmat.2024.155178
"Ion irradiation and examination of Additive friction stir deposited 316 stainless steel" Ching-Heng Shiau, Aishani Sharma, Zhihan Hu, Megha Dubey, Yu Lu, Lin Shao, Ramprashad Prabhakaran, Yaqiao Wu, Rajiv S. Mishra, Priyanka Agrawal, [2024] Materials & Design · DOI: 10.1016/j.matdes.2024.112730
"Effects of Carbon on Void Nucleation in Self-Ion–Irradiated Pure Iron" Lin Shao, Zhihan Hu, [2024] Nuclear Science and Engineering · DOI: 10.1080/00295639.2023.2224468
"Formation and dissolution of carbides and precipitates in self-ion irradiated HT9 alloy" Zhihan Hu, Yongchang Li, Cheng Sun, Stuart A. Maloy, Frank A. Garner, Lin Shao, Miguel Pena, [2024] Journal of Nuclear Materials · DOI: 10.1016/j.jnucmat.2023.154819
"Behavior and properties of helium cavities in ductile-phase-toughened tungsten irradiated with He+ ions at an elevated temperature" Libor Kovarik, Karen Kruska, Yucheng Fu, Zhihan Hu, Lin Shao, Wahyu Setyawan, Weilin Jiang, [2023] Materialia · DOI: 10.1016/j.mtla.2023.101789
"A quantitative method to determine the region not influenced by injected interstitial and surface effects during void swelling in ion-irradiated metals" Aaron French, Zhihan Hu, Adam Gabriel, Laura R. Hawkins, Frank A. Garner, Lin Shao, Yongchang Li, [2023] Journal of Nuclear Materials · DOI: 10.1016/j.jnucmat.2022.154140
"A method to predict texture effect on ion beam channeling analysis of polycrystals and the application to study the mosaic spreading effect in highly oriented pyrolytic graphite" Rijul Chauhan, Di Chen, Zhihan Hu, X. M. Wang, Lin Shao, Yongchang Li, [2022] Journal of Applied Physics · DOI: 10.1063/5.0088622

We propose a method to convert the channeling Rutherford backscattering spectrum yield map of a single crystal to a polycrystal through a matrix rotation technique. The rotation matrix is determined by the deviation of the crystal axial direction from the original z axis. The final yield map is created after averaging the rotated yields using the texture function as the weight factor. For highly oriented pyrolytic graphite (HOPG) exhibiting mosaic spread, the method leads to a Gaussian kernel averaging of the map obtained from a single crystal. The yield map of a single crystal is obtained by a simulation of ion trajectories in a potential field described by Moliere screened Coulomb potentials. Yield maps are calculated under variousσ values (standard deviations of mosaic spread). The simulated results are compared with experimental results obtained using 1.2 MeV alpha particle. σ is extracted through the best fitting, demonstrating that the method can be used to obtain texture details. The effects of mosaic spread on minimum yield χmin and the half-width at half maximum of angular scans ψ1/2 are systematically modeled and compared with previous theoretical equations. The study also shows that previous theoretical equations are valid only at small σ values. The proposed method can be applied to any type of polycrystal and is not limited to HOPG. It provides near-surface mosaic spread and crystallography information with a longitudinal depth resolution of tens of nanometers and is not influenced by grain shapes.

"Microstructural evolution and precipitation in γ-LiAlO2 during ion irradiation" Libor Kovarik, Zihua Zhu, Tamas Varga, Mark E. Bowden, Bethany E. Matthews, Zhihan Hu, Lin Shao, David J. Senor, Weilin Jiang, [2022] Journal of Applied Physics · DOI: 10.1063/5.0089865

Polycrystalline γ-LiAlO2 pellets were sequentially irradiated with 120 keV He+ and 80 keV D2+ ions to the fluences of 1 × 1017 and 2 × 1017 (He+ + D+)/cm2 at 573 K. Additional irradiation was performed to a fluence of 2 × 1017 (He+ + D+)/cm2 at 773 K. The irradiated pellets were characterized using scanning transmission electron microscopy, time-of-flight secondary ion mass spectrometry, and grazing incidence x-ray diffraction. Lattice damage, amorphization, and fractures are observed with no evidence for the formation of secondary-phase precipitates in the pellets irradiated up to an ion fluence of 2 × 1017 (He+ + D+)/cm2 at 573 K. In contrast, faceted precipitates with sizes larger than 100 nm formed in a pellet irradiated to 2 × 1017 (He+ + D+)/cm2 at 773 K. Analyses of the diffraction and composition data suggest that the precipitates have a spinel-type structure, likely a non-stoichiometric LiAl5O8 with Li depletion. This could be an intermediate phase with Li atoms at the octahedral and possibly tetrahedral sites as well. It is speculated that as the dose increases, Li loss will continue and the precipitates will approach a composition of alumina primarily in phases of α-Al2O3 and amorphized Al2O3.

"Helium ion irradiation effects on microstructure evolution and mechanical properties of silicon oxycarbide" Kaustubh Bawane, Zhihan Hu, Liuqing Yang, Youxing Chen, Lin Shao, Kathy Lu, Sanjay Kumar Devendhar Singh, [2022] Ceramics International · DOI: 10.1016/j.ceramint.2022.02.152
"Effect of Stress on Irradiation Responses of Highly Oriented Pyrolytic Graphite" Di Chen, SeungSu Kim, Rijul Chauhan, Yongchang Li, Lin Shao, Zhihan Hu, [2022] Materials · DOI: 10.3390/ma15103415 · ISSN: 1996-1944

The effect of stress on irradiation responses of highly oriented pyrolytic graphite (HOPG) was studied by combing molecular dynamics (MD) simulation, proton irradiation, and Raman characterization. MD simulations of carbon knock-on at energies < 60 eV were used to obtain average threshold displacement energies (E¯d) as a function of strain ranging from 0 to 10%. Simulations at a higher irradiation energy of 2–5 keV were used to study the effect of strain on damage cascade evolution. With increasing tensile strain, E¯d was reduced from 35 eV at 0% strain to 31 eV at 10% strain. The strain-reduced E¯d led to a higher damage peak and more surviving defects (up to 1 ps). Furthermore, high strains induced local cleavage around the cavities, as one additional mechanism of damage enhancement. Experimentally, HOPG film was folded, and the folded region with the maximum tensile stress was irradiated by a 2 MeV proton beam. Raman characterization showed significantly enhanced D to G modes in comparison to the stress-free irradiation. Based on the strain dependence of E¯d and the Kinchin–Pease model, a formula for displacement estimation under different tensile strains is proposed. The stress effects need to be considered in graphite applications in a reactor’s harsh environment where both neutron damage and stress are present.

"Behavior of helium cavities in ion-irradiated W-Ni-Fe ductile-phase toughened tungsten" Dalong Zhang, Dongsheng Li, Jaeyoung Heo, Zhiqiang Wang, Limin Zhang, Nicole Overman, Tamas Varga, Zhihan Hu, Xuemei Wang, Lin Shao, Wahyu Setyawan, Weilin Jiang, [2022] Journal of Nuclear Materials · DOI: 10.1016/j.jnucmat.2022.153565 · EID: 2-s2.0-85123929163 · ISSN: 0022-3115
"Effect of dpa rate on the temperature regime of void swelling in ion-irradiated pure chromium" Laura Hawkins, Aaron French, Yongchang Li, Zhihan Hu, Lingfeng He, Pengyuan Xiu, Michael Nastasi, Frank.A. Garner, Lin Shao, Adam Gabriel, [2022] Journal of Nuclear Materials · DOI: 10.1016/j.jnucmat.2022.153519 · EID: 2-s2.0-85123371456 · ISSN: 0022-3115
Source: ORCID/CrossRef using DOI