Article
Materials Science, Multidisciplinary
Hadi Ghaffarian, Ye-Eun Na, Dongchan Jang
Summary: In this study, the plastic deformation mechanism of lath boundary sliding in reduced-activation ferritic/martensitic (RAFM) steel was investigated using uniaxial micro-compression tests combined with crystallographic analysis. The results revealed that the amount of lath boundary sliding is controlled by various factors, including the crystallographic orientation of the lath boundary plane, the direction of Burgers vectors of interfacial dislocations, and the magnitude of resolved shear stress on the lath boundary plane. The effect of normal stress on the lath boundary plane was also explored.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Chemistry, Physical
Kseniya Bazaleeva, Alexander Golubnichiy, Anton Chernov, Andrey Ni, Ruslan Mendagaliyev
Summary: The study investigated an anomaly in martensitic transformation in complex alloyed steels and found the presence of martensitic two-peak splitting in highly alloyed steels. The anomaly was eliminated through high-temperature aging, and it was observed that heating the steel to 900 degrees Celsius can result in a two-stage transformation of austenite decomposition.
Article
Materials Science, Multidisciplinary
B. K. Kim, L. Tan, H. Sakasegawa, C. M. Parish, W. Zhong, H. Tanigawa, Y. Katoh
Summary: The study revealed that doping with Ni-58 resulted in greater strengthening contributions from loops and cavities, leading to higher hardening and lower ductility compared to Ni-60 doping in reduced-activation ferritic-martensitic steels under helium irradiation.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Nuclear Science & Technology
Michael Mahler, Giacomo Po, Yinan Cui, Nasr Ghoniem, Jarir Aktaa
Summary: The role of hierarchical defects microstructure of ferritic-martensitic steel Eurofer97 in determining hardening behavior is investigated using Dislocation Dynamics (DD) simulations. Material properties and dependence on temperature are determined, and microstructure-specific hardening parameters are extracted for simulating the properties of Eurofer97 at the engineering scale.
NUCLEAR MATERIALS AND ENERGY
(2021)
Article
Multidisciplinary Sciences
Osman Mamun, M. F. N. Taufique, Madison Wenzlick, Jeffrey Hawk, Ram Devanathan
Summary: Three probabilistic methodologies were developed to predict the long-term creep rupture life of ferritic-martensitic steels. The study identified the limitations of using probabilistic machine learning models and proposed improvements. Experimental results showed that Gaussian Process Regression performed better in terms of accuracy and uncertainty estimation.
SCIENTIFIC REPORTS
(2022)
Article
Materials Science, Multidisciplinary
Quanqiang Shi, Wei Yan, Yanfen Li, Naiqiang Zhang, Yiyin Shan, Ke Yang, Hiroaki Abe
Summary: The oxidation behavior of two Ferritic/Martensitic (F/M) steels, SIMP steel and P91 steel, was studied in high temperature and high pressure water environment. It was found that SIMP steel showed better oxidation resistance than P91 steel, possibly due to differences in microstructure.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
R. Hulse, C. P. Race
Summary: Neutron irradiation causes changes in the properties of zirconium alloys, including hardening and reduction in lattice parameter ratio with fluence. Atomistic simulations on dislocation loops in Zr reveal insights into their formation and evolution, suggesting that interstitial and vacancy loops are both energetically feasible. These findings provide important information on a phenomenon that is difficult to study experimentally.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Kang-Mook Ryu, Dae Geon Lee, Joonoh Moon, Chang-Hoon Lee, Tae-Ho Lee, Jae Sang Lee, Dong-Woo Suh
Summary: The study found that the addition of titanium in TaTi-RAFM and EUROFER97 steels slows down hydrogen diffusion and increases its solubility in the lattice. The activation energy of hydrogen trapping increases with re-austenitization and quenching, suggesting dislocations provide trap sites with higher activation energy than Ta-rich MC carbides.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Hao Shi, Hui Wang, Renate Fetzer, Annette Heinzel, Alfons Weisenburger, Kangli Wang, Adrian Jianu, Georg Mueller
Summary: By exposing three 9 wt% Cr ferrite/martensite steels to oxygen-controlled LBE, it was found that adding Si can decrease the thickness of the spinel layer, enhance the internal oxidation zone, and improve the scale adherence on Si-containing samples.
Article
Materials Science, Multidisciplinary
Lukas Kosek, Lucia Rozumova, Anna Hojna, Martina Pazderova
Summary: The performance of two steels, Grade91 and Eurofer97, were investigated after exposure to flowing liquid lead at 480°C. Both steels developed characteristic triple layer oxide growth following logarithmic kinetics. Eurofer97 oxidized faster with more material loss, while Grade91 formed a thick oxide scale with minimal detachment of the outer layer and lower material loss.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Review
Materials Science, Multidisciplinary
Jin-hua Zhou, Yong-feng Shen, Nan Jia
Summary: The strengthening mechanisms of RAFM steels include high-angle grain boundaries, subgrain boundaries, M23C6, and MX carbide precipitates, which can enhance high-temperature strength and improve creep properties. Additionally, methods such as oxide dispersion-strengthening and severe plastic deformation can effectively improve the performance of the steel, increasing creep life and overall strength.
INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Akihiko Kimura, Wei Sang, Wentuo Han, Kiyohiro Yabuuchi, Zongxi Xin, Junhua Luan, Peng Dou
Summary: The age-hardening behavior of oxide dispersion strengthened (ODS) ferritic steels with different Cr and Al contents was studied through Vickers hardness measurement and tensile tests after ageing at 475 degrees C for up to 900 hours. Atom probe tomography (APT) was used to investigate the evolution of nanometer-scale structure and chemistry. The results revealed that the age-hardening mechanism in ODS steels involves alpha-alpha' phase separation and/or the precipitation of (Al, Ti)-enriched f1 phases. The concentration and volume fraction of alpha' phase increased significantly with increasing Cr content, while the chemical compositions and volume fraction of f1 phases remained relatively constant during ageing.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Myeongkyu Lee, Geon Kim, Yunsong Jung, Sangjoon Ahn
Summary: The newly developed ferritic/martensitic steels FC92-B and -N showed the greatest swelling resistance, with FC92-N having a swelling rate of 0.005 %/dpa. The least swelling-resistant alloy was HT9, with a swelling rate of 0.048 %/dpa. The unique M2X precipitation in the FC92 series may be attributed to B and N alloying.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Metallurgy & Metallurgical Engineering
Li-dong Xia, Hao Chen, Zhi-gang Yang, Chi Zhang
Summary: Helium ion irradiation at 350 degrees C was performed to study the equilibrium segregation and radiation-induced segregation of Cr at grain boundaries in reduced activation ferritic/martensitic steels. The Cr concentration at grain boundaries was measured and analyzed, with results indicating that as temperature rises, equilibrium Cr segregation decreases monotonically, while RIS of Cr has a bell-shaped profile, increasing first and then decreasing. It was also found that at low and high temperatures, equilibrium segregation of Cr is higher than RIS; at intermediate temperatures, equilibrium Cr segregation is lower than RIS.
JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
C. Dai, P. Saidi, B. Langelier, Q. Wang, C. D. Judge, M. R. Daymond, M. Mattucci
Summary: Radiation-induced segregation of alloying elements to crystallographic defects is commonly observed in irradiated austenitic stainless steels. The interaction between solutes and defects affects the physical distribution of solutes, which in turn affects the formation, growth, and mechanical properties of defects. Atom probe tomography and molecular dynamics simulations were used in this study to investigate the distribution of solutes and stress fields at dislocation loops in 304L stainless steel. The results show that at higher temperatures, enrichment and depletion of certain alloying elements occur at dislocation loops, while no segregation is observed at lower temperatures. The simulations reveal the formation of Cr clusters and the enrichment or depletion of Ni atoms at different types of dislocation loops.
PHYSICAL REVIEW MATERIALS
(2022)