Article
Nanoscience & Nanotechnology
Qiuzhi Gao, Zhi Yuan, Qingshuang Ma, Liming Yu, Huijun Li
Summary: The effects of secondary normalizing treatment on the microstructure and mechanical properties of G115 steel were investigated. It was found that the width of martensitic lath decreases and the volume fraction of precipitates increases with increasing secondary normalizing temperature. Compared to single normalizing treatment, the yield strength, elongation, and impact toughness of G115 steel can be improved after secondary normalizing treatment.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Stefan Zeisl, Nele Van Steenberge, Ronald Schnitzer
Summary: One class of maraging steels is strengthened by the precipitation of beta-NiAl and eta-Ni3Ti intermetallic phases during aging heat treatment. To establish a meaningful structure-property relationship, the individual precipitation strengthening effect of each phase needs to be determined. Atom probe tomography was utilized in this study to determine the spacing between precipitates and calculate the individual strength contribution of the beta and eta phases using a model for precipitate-dislocation interactions. The results showed that the combined precipitation strengthening effect of the beta and eta phases is close to 1000 MPa, and the relative strengthening effect of each phase is influenced by the Ti and Al concentration.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Huan Xue, Yansong Zhang, Min Zhu, Xiyan Yin, Wenqian Zhang, Shengnan Liu
Summary: The study investigated different alloy compositions of wear-resistant steels and found that ARIV exhibited higher strength and hardness, relatively uniform toughness distribution, smaller martensite lath width, and more precipitates below 50 nanometers.
MATERIALS RESEARCH EXPRESS
(2021)
Article
Chemistry, Physical
Hongtu Xu, Tiantai Tian, Jiahao Zhang, Liqun Niu, Hongbin Zhu, Xingtao Wang, Qi Zhang
Summary: The study developed an accurate modified constitutive model to describe the hot deformation behavior of 25CrMo4 steel. The coupling effect of temperature and strain rate on the material's mechanical properties was analyzed, and dynamic recrystallization was found to be the main mechanism for macroscopic softening. The modified model showed improved prediction accuracy compared to the original model.
Article
Materials Science, Multidisciplinary
Yankun Wang, Qingshuang Ma, Qiuzhi Gao, Hailian Zhang, Huijun Li, Ziyun Liu, Minglong Gong
Summary: This study investigates the microstructure evolution and mechanical properties of high-Cr martensitic heat-resistant steel under different tempering conditions, and discusses the precipitation and strengthening behavior of M23C6 carbides. The results show that the contribution of M23C6 carbides to yield strength varies with tempering temperature.
Article
Materials Science, Multidisciplinary
Rongchuang Chen, Shiyang Zhang, Min Wang, Xianlong Liu, Fei Feng
Summary: It is important to develop constitutive models that reflect microstructure evolution for accurately predicting material flow and microstructure evolution during forming processes. In this study, a constitutive model considering microstructure evolution was proposed and found to improve prediction precision when the stress-strain curve was modeled as exponential in the work-hardening stage. Additionally, models describing recrystallization kinetics and average grain size were constructed, enabling higher accuracy in predicting stress-strain curves.
Article
Materials Science, Multidisciplinary
C. G. Shang, M. L. Wang, Z. C. Zhou, Y. H. Lu
Summary: In this study, creep tests were conducted on 9Cr3W3Co steel at 650°C under 155-220 MPa in air and water vapor environments. The results showed that water vapor did not affect the creep deformation mechanism, but influenced the creep behaviors and life depending on the stress level. High stress levels in water vapor resulted in a decrease in steady-creep rate and an increase in steady-creep stage time, while low stress levels led to an increase in steady-state creep rate and a decrease in the time of steady-state creep stage. The interaction of different stresses and creep environments induced different forms of creep damage, affecting the creep fracture process and creep life.
MATERIALS CHARACTERIZATION
(2023)
Article
Multidisciplinary Sciences
Manas Vijay Upadhyay, Meriem Ben Haj Slama, Steve Gaudez, Nikhil Mohanan, Lluis Yedra, Simon Hallais, Eva Heripre, Alexandre Tanguy
Summary: Research on a 316L stainless steel shows that non-oxide precipitates can form during Laser Metal Deposition (LMD), a type of directed energy deposition AM technique. These precipitates form during solidification/cooling at temperatures >= 0.75T(m) and temperature rates <= 10(5) K/s. This phenomenon is consistent with existing literature and is not observed during Selective Laser Melting (SLM).
SCIENTIFIC REPORTS
(2021)
Article
Materials Science, Multidisciplinary
Man Liu, Jun Wang, Qi Zhang, Haijiang Hu, Guang Xu
Summary: The study reveals that the optimal mechanical properties of Q&P steels do not necessarily correspond to the highest volume fraction of retained austenite. Quenching at the fine martensite start temperature can achieve a Q&P steel with better elongation at the expense of slightly lower yield strength and tensile strength.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Nanoscience & Nanotechnology
Jingwen Zhang, Liming Yu, Qiuzhi Gao, Chenxi Liu, Zongqing Ma, Huijun Li, Yongchang Liu, Hui Wang
Summary: This study systematically investigated the influences of prior cold deformation on creep behavior, microstructure evolution, and fracture mechanism of the novel G115 steel. It was found that moderate deformation reduction could significantly prolong the creep rupture life, while higher deformation reduction could shorten it. For deformation reduction within 30%, the creep damage was identified as microstructural degradation with limited contribution from necking.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Peter Birnbaum, Stefan Pilz, Kai Neufeld, Andreas Kunke
Summary: A constitutive model was developed to characterize the static recrystallization and grain size evolution of press-hardening steel 22MnB5. Isothermal stress relaxation tests were conducted to study the effects of temperature, prestrain, and strain rate on the kinetics of static recrystallization. The results showed that temperature and prestrain had significant influences on the recrystallization kinetics, while strain rate had a relatively small impact. Microstructural analysis and electron backscatter diffraction were also performed to examine the effects of forming parameters on grain size and martensite morphology.
Article
Metallurgy & Metallurgical Engineering
Zhong-yi Chen, Zheng-zong Chen, Dong-xu Kou, Yong-qing Li, Yong-lin Ma, Yi-ming Li
Summary: Based on the thermal simulation method, a systematic analysis was conducted on the effect of welding peak temperature and cooling time on microstructure, precipitates, substructure, and microhardness of the reheated coarse-grained heat-affected zone (CGHAZ) of G115 novel martensitic heat-resistant steel. The study found differences in microstructure, hardness, and precipitate content in different regions of the reheated CGHAZ.
JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Anjin Liu, Lin Wang, Xingwang Cheng, Zixuan Ning, Lei Pan
Summary: The hot deformation behavior and microstructure evolution of newly developed as-cast high-density steel were investigated. The steel exhibited higher activation energy and an increase in the degree of dynamic recrystallization with increasing temperature and decreasing strain rate.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Materials Science, Multidisciplinary
Jingwen Zhang, Liming Yu, Ran Ding, Chenxi Liu, Zongqing Ma, Huijun Li, Yongchang Liu, Qiuzhi Gao, Hui Wang
Summary: This study systematically investigated the creep deformation, microstructure evolution, and rupture mechanism of the G115 welded joint to promote its application in ultra-supercritical power plants. The G115 welded joint exhibited superior creep strength compared to other steels. The deformation mechanism was found to be closely associated with the stress levels. Short-term creep under higher stress resulted in rupture within the base metal, while long-term creep under lower stress led to brittle cracking within certain heat-affected zones. The study also highlighted the synergistic action of back stress and dislocation motion in enhancing the creep resistance of the G115 welded joint.
MATERIALS CHARACTERIZATION
(2023)
Article
Metallurgy & Metallurgical Engineering
He Huansheng, Yu Liming, Liu Chenxi, Li Huijun, Gao Qiuzhi, Liu Yongchang
Summary: Improving the steam temperature and pressure of thermal power boilers can increase coal-fired efficiency and reduce harmful gas emissions. In light of dwindling fossil resources and the worsening global greenhouse effect, developing new heat-resistant materials for ultra super-critical units at 650 degrees C and higher becomes crucial. Martensitic heat-resistant steel G115, based on P92 steel used in 600 degrees C units, is a promising candidate due to its great thermal conductivity, good fatigue resistance, and low cost. This paper introduces the chemical composition and microstructure of G115 steel, summarizes research progress in microstructure stability, creep performance, fatigue resistance, steam oxidation resistance, and industrial pipe production, with a focus on the role of Cu-rich phase in G115 steel. Finally, key points for future research on G115 steel are proposed.
ACTA METALLURGICA SINICA
(2022)
Article
Materials Science, Multidisciplinary
Youwei Xu, Hongyang Jing, Lianyong Xu, Yongdian Han, Lei Zhao
Article
Construction & Building Technology
Lei Zhao, Junjie Liu
BUILDING AND ENVIRONMENT
(2020)
Article
Mechanics
Lianyong Xu, Lei Zhao, Zhifang Gao, Yongdian Han, Hongyang Jing
ENGINEERING FRACTURE MECHANICS
(2020)
Article
Construction & Building Technology
Wei Chen, Lianyong Xu, Lei Zhao, Yongdian Han, Hongyang Jing, Yang Zhang, Yuan Li
JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH
(2020)
Article
Engineering, Manufacturing
Danyang Lin, Lianyong Xu, Hongyang Jing, Yongdian Han, Lei Zhao, Fumiyoshi Minami
ADDITIVE MANUFACTURING
(2020)
Article
Physics, Fluids & Plasmas
Runjie Song, Lei Zhao, Zhangfeng Huang
PHYSICAL REVIEW FLUIDS
(2020)
Article
Mechanics
Ming Dong, Lei Zhao
Summary: This paper develops a large-Reynolds-number asymptotic theory to describe the impact of a localized roughness element on inviscid first and second Mack modes in supersonic or hypersonic boundary layers. It is found that the roughness affects the oscillation frequency of the Mack modes, and identifies the critical frequency at which the roughness transitions from stabilizing to destabilizing effects. An improved asymptotic theory is also proposed to enhance the accuracy of predictions, confirmed through numerical simulations even with significant roughness height compared to the boundary layer thickness.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Physics, Fluids & Plasmas
Lei Zhao, Ming Dong
Summary: This paper investigates the impact of local surface temperature strips on oncoming inviscid Mack instability in supersonic or hypersonic boundary layers, revealing that temperature strips play an equivalent role as roughness elements but with more complex interactions with Mack modes. The research findings suggest that heating strips enhance or suppress Mack modes depending on frequencies relative to a critical value, while cooling strips have the opposite effect. The asymptotic predictions align closely with Harmonic linearized Navier-Stokes calculations and direct numerical simulations, especially at low wall temperatures.
PHYSICAL REVIEW FLUIDS
(2022)
Article
Mechanics
Qinyang Song, Lei Zhao
Summary: This paper investigates the effects of porous coating on the control strategy for hypersonic boundary layers. Using the harmonic linearized Navier-Stokes approach, the scattering effect at the junctions between solid and porous walls is studied. Results show that a decrease in wall temperature enhances the scattering effect.
Article
Mechanics
Runjie Song, Ming Dong, Lei Zhao
Summary: In this paper, the authors investigate the oblique-breakdown regime in low-Mach-number supersonic boundary layers, specifically focusing on the additional amplification of the streak mode generated by the direct interaction of the introduced oblique modes. Through weakly nonlinear analysis and quantitative NPSE calculations, the mechanism behind this phenomenon is well explained. The important role of the streak mode in triggering the transition onset is also identified.
Article
Engineering, Aerospace
Youde Xiong, Lei Zhao, Jie Wu
Summary: In this study, the disturbance resonance in the postshock zone of a blunt body is characterized using both experimental and theoretical approaches. The resonance mechanism on the surface is found to be dominated by the interference between the initial diverging sound wave and the shock-reflected sound wave, while in the space, the stationary wave formed by the initial diverging sound wave and the body-reflected wave plays a leading role.
Article
Mechanics
Lei Zhao, Jianhong He, Ming Dong
Summary: This paper examines the local receptivity of the inviscid Mack modes in hypersonic boundary layers affected by factors such as a surface heating or cooling source and a freestream acoustic wave. The analysis reveals the importance of the interaction between the induced mean-flow distortion and the acoustic signature in the wall layer. The asymptotic predictions are found to be accurate even at high Reynolds numbers.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Lei Zhao, Ming Dong
Article
Mechanics
Runjie Song, Lei Zhao, Zhangfeng Huang
Proceedings Paper
Computer Science, Theory & Methods
Jie Chen, Jihui Ou, Lei Zhao
31ST INTERNATIONAL SYMPOSIUM ON RAREFIED GAS DYNAMICS (RGD31)
(2019)
Article
Nanoscience & Nanotechnology
Ahmad Mirzaei, Peter D. Hodgson, Xiang Ma, Vanessa K. Peterson, Ehsan Farabi, Gregory S. Rohrer, Hossein Beladi
Summary: This study investigated the influence of parent austenite grain refinement on the intervariant boundary network in a lath martensitic steel. It found that refining the parent austenite grain led to a decrease in the fraction of certain boundaries in the martensite and an increase in the connectivity of low energy boundaries, ultimately improving the impact toughness.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
N. L. Church, C. E. P. Talbot, L. D. Connor, S. Michalik, N. G. Jones
Summary: Metastable beta Ti alloys based on the Ti-Nb system have attracted attention due to their unique properties. However, the unstable cyclic behavior of these alloys has hindered their widespread industrial use. Recent studies have shown that internal stresses, including those from dislocations, may be responsible for this behavior. This study demonstrates that inter-cycle thermal treatments can mitigate the unstable cyclic behavior, providing a significant breakthrough in our understanding of Ti-Nb superelastic materials.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Di Zhao, Chenchen Zhao, Ziyang Xiu, Jiuchun Yan
Summary: This study proposes a novel strategy for achieving the bonding of SiC ceramic and Al alloy using ultrasound. The ultrasound promotes the dissolution of Al into the solder, activating the solder and triggering the interfacial reaction between SiC ceramic and solder. With increasing ultrasonic duration, the bonding between SiC and Al transitions from partial to full metallurgical bonding.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Kang Du, Yang Zhang, Guangda Zhao, Tao Huang, Liyuan Liu, Junpeng Li, Xiyu Wang, Zhongwu Zhang
Summary: This paper systematically investigated the evolution of microstructure in Fe-Ni-Co-Al polycrystalline alloys and its effects on mechanical properties. The results revealed that the migration of grain boundaries in different processes is driven by different factors, which impacts the grain orientation and precipitate formation. In the process of directional recrystallization, grains with specific orientations grow in the grain boundary region and form the dominant orientation, while grains with lower migration rate form the minor orientation. The alloy produced through directional recrystallization exhibited good recoverable strain and superelastic strain, while the alloy produced through solid solution treatment showed no evident superelastic behavior.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Edohamen Awannegbe, Liang Chen, Yue Zhao, Zhijun Qiu, Huijun Li
Summary: This study employed laser metal deposition to additively manufacture Ti-15Mo wt% alloy, and subsequently subjected it to post-fabrication uniaxial thermomechanical processing. The results showed that different zones in the microstructure remained after processing, and deformation mechanisms mainly involved slip and martensite formation. The compressive mechanical properties were found to be dependent on strain rate, with higher flow stress and compressive strength observed at higher strain rates. Grain structure homogenisation was not achieved, leading to anisotropic tensile properties.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Reza Khatib Zadeh Davani, Enyinnaya George Ohaeri, Sandeep Yadav, Jerzy A. Szpunar, Jing Su, Michael Gaudet, Muhammad Rashid, Muhammad Arafin
Summary: This research aims to investigate the effect of roughing and finishing reductions on crystallographic texture. The results show significant heterogeneity in the centerline region, with higher intensity of certain textures. Drop Weight Tear Test indicates that steel specimens with lower and medium reductions exhibit superior low-temperature impact toughness compared to steel with higher reductions. The electrochemical hydrogen charging experiments confirm the presence of internal hydrogen cracks only in steel with lower and medium reductions.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Flavio De Barbieri, Denis Jorge-Badiola, Rodrigo Allende, Karem Tello, Alfredo Artigas, Franco Perazzo, Henry Jami, Juan Perez Ipina
Summary: This study examines the effect of Cr additions on the mechanical behavior of TWIP steel at temperatures ranging from 25°C to 350°C. The results indicate that different temperature-dependent strengthening mechanisms, including mechanical twinning, Dynamic Strain Aging, and slip bands, are at play. The stacking fault energy (SFE) influences the percentage of mechanical twinning, which in turn affects the strain hardening rate.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Hanlin Peng, Siming Huang, Ling Hu, Bingbing Luo, Liejun Li, Ian Baker
Summary: This study explores the weldability, microstructures, and mechanical properties of two L1(2)-nanoparticle-strengthened medium-entropy alloys after electron beam welding (EBW). The results show that strong yet ductile defect-free joints were produced, with larger grain sizes in the fusion zones compared to the heat-affected zones and base materials. Both EBWed MEAs exhibited high yield strengths, high ultimate tensile strengths, and good fracture strains at 77 K. The V-doping improved the cryogenic mechanical properties of the TMT MEA.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Yongxin Wang, Lei Chen, Lizi Shao, Shuo Hao, Motomichi Koyama, Xingzhou Cai, Xiaocong Ma, Miao Jin
Summary: This study investigated the tensile deformation behavior of an Mn-N bearing lean duplex stainless steel with metastable austenite. The results showed that the strain rate had significant influence on the work hardening, strain-induced martensitic transformation, and fracture mechanism.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Jong Woo Won, Seulbi Lee, Hye-Jeong Choe, Yong-Taek Hyun, Dong Won Lee, Jeong Hun Lee
Summary: Cold-rolled pure titanium showed improved sheet formability after undergoing cryogenic-deformation treatment. This treatment increased the thinning capability of the titanium and suppressed cracking during sheet forming. The formation of twins during deformation contributed to high thinning capability and increased strength through grain refinement and dislocation accumulation.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Handong Li, Lin Su, Lijuan Wang, Yanbin Jiang, Jiahui Long, Gaoyong Lin, Zhu Xiao, Yanlin Jia, Zhou Li
Summary: Homogenization heat treatment is a key procedure in controlling the second phase, enhancing composition uniformity, and workability of as-cast Cu-15Ni-8Sn alloy. This study found that electropulsing treatment (EPT) can significantly reduce treatment temperature and time, improve elongation and overall mechanical properties of the alloy.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Yuxuan Wang, Juntao Zou, Lixing Sun, Yunfei Bai, Zhe Zhang, Junsheng Cheng, Lin Shi, Dazhuo Song, Yihui Jiang, Zhiwei Zhang
Summary: A novel mechanical-heat-electricity synergistic method was proposed to enhance the mechanical properties of Cu-15Sn-0.3Ti alloy by forming annealing twins (ATs). The combination method of Rotary swaging (RS) and Electric pulse treatment (EPT) successfully induced recrystallization and refinement of the microstructure, leading to a significant increase in the strength of the alloy within a short time.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Zhiyi Ding, Jiangtao Xie, Tong Wang, Aiying Chen, Bin Gan, Jinchao Song
Summary: This study demonstrated the Ta-induced strengthening of CoCrNi-AlTi MEAs using nanoscale heterogeneous coherent precipitates. The addition of Ta and aging treatments significantly enhanced the mechanical properties of the alloy, including yield strength, ultimate tensile strength, and elongation.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Z. Y. You, Z. Y. Tang, B. Wang, H. W. Zhang, P. Li, L. Zhao, F. B. Chu, H. Ding
Summary: The mechanical properties and microstructural evolution of C-doped TRIP-assisted HEA under dynamic loading conditions were systematically investigated in this study. The results showed that dynamic tensile deformation led to an increase in yield strength and a decrease in ultimate tensile strength, with a trend towards increased total elongation. The primary deformation mechanisms shifted from TRIP and TWIP effects to deformation twinning and dislocations. The presence of carbides formed through C-doping hindered dislocation slip and promoted the activation of multiple twinning systems.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Feng Qin, Feihu Chen, Junhua Hou, Wenjun Lu, Shaohua Chen, Jianjun Li
Summary: Plastic instability in strong multilayered composites is completely suppressed by architecting nanoscale BCC Nb crystalline-amorphous CuNb interfaces.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)