Article
Materials Science, Multidisciplinary
Yu Tian, Hao Yu, Tao Zhou, Kun Wang, Zimeng Zhu
Summary: This study reveals the precipitation behavior and morphological characteristics of MX precipitates in deformed Ti-V-Nb multi-microalloyed steels, introducing the L parameter model for evaluating the shape of precipitates. The evolution rules of precipitate morphology provide insights for developing high-performance microalloyed steels.
MATERIALS CHARACTERIZATION
(2022)
Article
Materials Science, Multidisciplinary
Lijuan Cui, Yong Dai, Stephan S. A. Gerstl, Manuel A. Pounchon
Summary: This study aims to determine the effects of irradiation on the MX phase of Eurofer 97 and F82H. Atom probe tomography was used to reveal the irradiation-induced changes in MX phase, including changes in chemical composition and interface segregation. The results showed that the MX phase undergoes an initial transformation to Z-phase and dissolution at the edge under the current irradiation conditions.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Zhao Shen, Xiaoqin Zeng, Shengchuan Wu, Hongbing Yu, Benjamin M. Jenkins, Phani Karamched, Michael P. Moody, Jianqiang Zhang, You Wang, Sergio Lozano-Perez
Summary: This study reveals that the internal oxide precipitates in Fe-9Cr ferritic steel and Fe-17Cr-9Ni austenitic steel exposed to 600°C deaerated steam for 600 hours have needle-like and near-spherical morphology. The morphology of these precipitates is controlled by the interface structure between the metal matrix and the internal oxide, which is influenced by the crystallographic structure and orientation relationship of the two phases. The results suggest the potential to manipulate the distribution, morphology, and interface structure of internal oxide precipitates for better high-temperature oxidation resistance.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Crystallography
Vlastimil Vodarek, Jan Holesinsky, Zdenek Kubon, Renata Palupcikova, Krystof Hradecny, Petra Vanova, Josef Hlinka
Summary: This study aims to characterize the modified Z-phase in vanadium-bearing austenitic steels, including its crystallography, thermodynamic and dimensional stability, precipitation kinetics, and solvus temperature. The study found that the modified Z-phase has high thermodynamic stability, but more data are needed to evaluate its long-term dimensional stability in engineering applications.
Article
Physics, Applied
Yunfei Du, Guodong Li, Li Zhang, Zhijie Xin, Hongbin Miao, Meini Yuan, Huihu Lu
Summary: In this study, the influence of various austenitizing temperatures on the microstructure and mechanical properties of Cr-Mo-Ni-V steels was explored. SEM and EDS analyses were used to investigate the dissolution of primary carbides during quenching and the precipitation behavior of carbides during tempering. It was found that increasing the austenitizing temperature resulted in the dissolution of VC into the matrix and a weakening of the pinning effect of VC on prior austenite grains. The dissolved V in the quenched condition retarded the carbide precipitation during tempering. With increasing austenitizing temperature, both tensile strength and elongation of tempered steels as well as impact toughness were increased.
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2022)
Article
Materials Science, Multidisciplinary
Xiang Liu, Luca Capriotti, Tiankai Yao, Jason M. Harp, Michael T. Benson, Yachun Wang, Fei Teng, Lingfeng He
Summary: The annular metallic fuel design eliminates the liquid sodium bond between the fuel and the cladding, providing back-end fuel cycle and other benefits, presenting new features. Negligible amounts of lanthanides were found in the FCCI layer in the investigated annular fuel, with most retained in the newly formed UZr 2 phase in the fuel center region.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Man Wang, Hongying Sun, Zhangjian Zhou
Summary: Two kinds of Fe-18Ni-12Cr-based alumina-forming austenitic (AFA) steels were prepared by vacuum induction melting, with one variant (18-12-AlNb) showing superior creep properties compared to the other (18-12-Al) due to the addition of Nb promoting the formation of Laves-Fe-2(Mo,Nb) and nanoscale NbC.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Crystallography
Anqi Liu, Fei Zhao, Wensen Huang, Yuanbiao Tan, Yonghai Ren, Longxiang Wang, Fahong Xu
Summary: GH4169 alloy is strengthened primarily through precipitation, with heat treatment being crucial for regulating the precipitates. However, the effects of aging temperature on the microstructure and properties of GH4169 have not been thoroughly studied. This study investigated the impact of aging temperature on precipitates and mechanical properties of GH4169 alloy using various techniques. The results showed that increasing aging temperature led to larger gamma and gamma ' phases and promoted the precipitation of delta phase at grain boundaries. The alloy aged at 750 degrees C exhibited the highest yield strength and the Portevin-Le Chatelier effect weakened as the aging temperature increased.
Article
Nanoscience & Nanotechnology
Xueyun Gao, Haiyan Wang, Lei Xing, Cainv Ma, Yiming Li, Gang Sha, Huiping Ren
Summary: The simultaneous improvement in strength and ductility of ferrite/martensite dual-phase (DP) steels was studied by investigating the synergistic effects of ultrafine grains and nano Cu-rich precipitates. Through experimental methods and simulations, it was found that a 75% reduction in warm deformation resulted in finer grains and higher tensile strength, with an optimal mechanical properties of yield strength of 876 +/- 13 MPa, tensile strength of 976 +/- 15 MPa, and total elongation of 15.2%. Additionally, the precipitation of nano Cu-rich precipitates contributed to an increase in strength of approximately 300 MPa.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Xueyun Gao, Haiyan Wang, Lei Xing, Cainv Ma, Yiming Li, Gang Sha, Huiping Ren
Summary: The simultaneous improvement in strength and ductility of ferrite/martensite dual-phase (DP) steels was studied by investigating the synergistic effects of ultrafine grains and nano-size Cu-rich precipitates. It was found that a 75% reduction in warm deformation led to finer grains and higher tensile strength. Crystal plasticity (CP) simulations showed that the heterogeneous distribution of martensite resulted in strong strain and stress partitioning, facilitating early damage nucleation. The strengthening effect of precipitation from nano Cu-rich precipitates was also evaluated, contributing to an approximately 300 MPa increase in strength in the steels.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
M. Harwarth, G. Chen, R. Rahimi, H. Biermann, A. Zargaran, M. Duffy, M. Zupan, J. Mola
Summary: The age hardenability of Al-alloyed lightweight stainless steels with different Ni concentrations was studied, showing significant impact on microstructures and hardening response. Hardness measurements indicated significant hardening at 350 degrees Celsius, while tensile elongation in the aged condition was negatively influenced by soft ferrite regions. Guidelines for the development of a new family of lightweight precipitation-hardenable steels were provided.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
M. Kreins, J. Wilkes, S. Wesselmecking, U. Krupp
Summary: The Bauschinger effect in austenitic-ferritic duplex stainless steel 1.4462 was investigated, and it was found that alpha ' precipitates formed in the ferritic phase significantly enhance the Bauschinger effect, contrary to the general belief. The presence of these precipitates increases the phase difference between austenite and ferrite, leading to enhanced deformation incompatibility and local dislocation density gradients. Despite their small size and coherence, the alpha ' precipitates generate long-range back stresses that contribute to the Bauschinger effect.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Nuclear Science & Technology
Wen Zeng, Ming Zhou, Mei Yang, Risheng Qiu
Summary: The influence of Zr content ranging from 0 to 1.36 wt.% on the microstructure and mechanical properties of 12Cr ferritic/martensitic steels was investigated. It was found that Zr acts as a ferrite-forming alloy element in the steels, leading to an increase in the proportion of ferrite phase with increasing Zr content, while decreasing strength but increasing ductility.
FUSION ENGINEERING AND DESIGN
(2022)
Article
Metallurgy & Metallurgical Engineering
Wen Zeng, Ming Zhou, Mei Yang, Risheng Qiu, Xianfu Luo
Summary: The influence of Zr content on the high-temperature oxidation resistance of 12Cr ferritic/martensitic steels is investigated. The results show that the addition of Zr improves the oxidation resistance. The oxide layer formed on the surface of steels mainly consists of MnCr2O4 and Cr2O3, and the addition of Zr promotes the formation of MnCr2O4 and reduces its growth rate. The improved oxidation resistance is attributed to the formation of a dense outer oxide layer, which inhibits oxygen diffusion.
STEEL RESEARCH INTERNATIONAL
(2023)
Article
Metallurgy & Metallurgical Engineering
Li Xiaolin, Liu Linxi, Li Yating, Yang Jiawei, Deng Xiangtao, Wang Haifeng
Summary: In recent decades, there has been a push to increase the operating temperature of steam generators to the ultra-supercritical regime. However, creep-resistant alloys face the challenge of coarsening of M23C6 and Laves phases during long-term service. Therefore, restricting the formation of easily coarsened precipitates is significant.
ACTA METALLURGICA SINICA
(2022)
Article
Engineering, Mechanical
H. K. Danielsen, F. Gutierrez Guzman, K. V. Dahl, Y. J. Li, J. Wu, G. Jacobs, G. Burghardt, S. Faester, H. Alimadadi, S. Goto, D. Raabe, R. Petrov
Article
Engineering, Mechanical
Carsten Jorn Rasmussen, Soren Faester, Somrita Dhar, Jesper Viggo Quaade, Manuel Bini, Hilmar Kjartansson Danielsen
Article
Materials Science, Multidisciplinary
H. K. Danielsen, A. J. Carrasco, S. Faester, K. Dah, F. Gutierrez Guzman, P. Sauvage, G. Jacobs
MATERIALS CHARACTERIZATION
(2019)
Article
Engineering, Mechanical
H. K. Danielsen, F. Gutierrez Guzman, M. Muskulus, B. H. Rasmussen, M. Shirani, D. Cornel, P. Sauvage, J. Wu, R. Petrov, G. Jacobs
Article
Engineering, Mechanical
S. Dhar, H. K. Danielsen, S. Faester, C. J. Rasmussen, D. Juul Jensen
Article
Engineering, Mechanical
Somrita Dhar, Hilmar K. Danielsen, Soren Faester, Carsten Rasmussen, Yubin Zhang, Dorte Juul Jensen
Article
Materials Science, Multidisciplinary
S. Dhar, J. Ahlstrom, X. Zhang, H. K. Danielsen, D. Juul Jensen
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2020)
Article
Materials Science, Multidisciplinary
Somrita Dhar, Hilmar K. Danielsen, Ruqing Xu, Yubin Zhang, Flemming Bjerg Grumsen, Carsten Rasmussen, Dorte Juul Jensen
Summary: The study investigated residual stress within a worn manganese steel railway crossing, using laboratory X-rays and synchrotron X-ray diffraction. Significant compressive stress was found on the rail running surface, with local strains existing throughout the depth investigated. The relationships between residual stress, plastic deformation, and crack formation were analyzed, discussing the potentials and limitations of the two experimental methods for investigating residual stress in large engineering components.
MATERIALS SCIENCE AND TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
H. K. Danielsen, C. Hong, O. Mishin
Summary: White etching cracks and other microstructural features were studied in two 100Cr6 steel bearings that failed after several years of service in wind turbines. Cracks were found to propagate primarily through prior austenite grains in the tempered martensite structure, with structural refinement of carbide particles occurring at a late stage of white etching matter formation.
Article
Engineering, Mechanical
H. K. Danielsen, F. Gutierrez Guzman, S. Faester, M. Shirani, B. H. Rasmussen, M. Linzmayer, G. Jacobs
Summary: This study investigates the impact of different bearing materials, quality, and roughness on the resistance to White Etch Cracking (WEC) through accelerated laboratory tests. The results show that the test method can reliably induce WEC in commercially available washers. Changes in roughness values did not significantly affect the time to failure, while through hardened bearing steel with low inclusion content exhibited longer failure time compared to the baseline. Black oxide coating on hardened washers did not improve WEC life, as the coating wore away during testing. However, carbo-nitrided washers with two different types demonstrated significantly longer time to failure, with one type showing high resistance to WEC formation.
Article
Engineering, Mechanical
Iman Shakeri, Hilmar K. Danielsen, Adrien Tribhou, Soren Faester, Oleg Mishin, Martin A. Eder
Summary: This study investigates the impact of manufacturing defects induced by thread rolling on the high-cycle fatigue life of M30 class 10.9 stud bolts. The high-cycle fatigue tests of two batches of seemingly identical bolts reveal significant differences in fatigue performance. Scanning electron microscopy characterization shows a clear correlation between the defect size, in the form of rolling-induced microcracks in the thread root, and the fatigue life of the investigated bolts. Numerical fatigue analysis agrees well with experimental data. Electron backscatter diffraction is used to determine the characteristic length of microstructurally short defects in the tempered martensite microstructure. These results shed light on the critical manufacturing defect sizes in bolts, which is an essential parameter for quality control in the manufacturing process.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Multidisciplinary Sciences
Soren Faester, Hilmar K. Danielsen
Proceedings Paper
Materials Science, Multidisciplinary
K. T. Hansen, S. Faester, A. Natarajan, O. V. Mishin, H. K. Danielsen, D. Juul Jensen, P. Klit
38TH RISO INTERNATIONAL SYMPOSIUM ON MATERIALS SCIENCE
(2017)
Proceedings Paper
Materials Science, Multidisciplinary
S. Dhar, Y. Zhang, R. Xu, H. K. Danielsen, D. Juul Jensen
38TH RISO INTERNATIONAL SYMPOSIUM ON MATERIALS SCIENCE
(2017)
Proceedings Paper
Materials Science, Multidisciplinary
Hilmar K. Danielsen, Fang Liu
38TH RISO INTERNATIONAL SYMPOSIUM ON MATERIALS SCIENCE
(2017)
