Article
Materials Science, Multidisciplinary
Yong Li, Lei Hu, Jialing Yan, Xiangyu Ji, Wanli Wang
Summary: The study used finite element method to investigate the impact of structural induced stress on creep evolution in pipe to elbow welds. The results showed that compressive axial stress accelerated creep strain near the outer surface of the pipe, while tensile axial stress accelerated creep strain near the inner surface. The findings are significant for understanding the behavior of welded joints in ultra-supercritical boilers.
Article
Materials Science, Multidisciplinary
C. G. Shang, M. L. Wang, Z. C. Zhou, K. Yagi, Y. H. Lu
Summary: In this study, uniaxial creep tests were conducted on P92 steel at 650 degrees C under different applied stresses. The microstructure evolution and its effect on the corresponding creep behaviors were investigated. It was found that different stress levels resulted in different creep behaviors due to the evolution of hierarchical martensite structure and precipitates, as well as their interaction with dislocations.
MATERIALS CHARACTERIZATION
(2023)
Article
Nanoscience & Nanotechnology
Wi-Geol Seo, Jin-Yoo Suh, Abhishek Singh, Jae-Hyeok Shim, Hansang Lee, Keunbong Yoo, Shi-Hoon Choi
Summary: This study investigated the microstructural development of the heat-affected zone in P92 heat-resistant steel during creep deformation in cross-weld specimen. It found that the FGHAZ II region, defined as a major change in microstructure during creep deformation, played a crucial role in cavity formation and fracture.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Yuxuan Song, Yi Ma, Haofeng Chen, Zhibo He, Hu Chen, Taihua Zhang, Zengliang Gao
Summary: This study investigated the creep-fatigue interactions on the long-term service damage of P92 welded joint by conducting tensile and compressive tests under different applied strains. Using nanoindentation, the local mechanical properties of the welded joint were examined, while scanning electron microscope was used to analyze fracture morphologies and internal defects after CF tests, revealing the effects of holding type on the local creep behavior and fracture mechanism of the welds.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Mechanical
Ning Gao, Wei Zhang, Peng Yin, Fei Liang, Guodong Zhang, Xianxi Xia, Yanfen Zhao, Changyu Zhou
Summary: High temperature multiaxial fatigue tests were performed at 600 degrees C with different strain amplitudes and strain ratios. The cyclic deformation and damage mechanisms were analyzed using dynamic strain ageing (DSA) analysis and microstructure characterization. The results indicate that increasing strain amplitude and strain ratio accelerate cyclic softening. The DSA behavior depends on strain amplitude, strain ratio, and loading direction. Moreover, increasing strain amplitude promotes subgrain growth and dislocation structure transformation, while increasing strain ratio promotes planar slip of dislocation.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Hermann Riedel, Gerhard Maier, Heiner Oesterlin
Summary: Current methods proposed by codes and standards to address creep-fatigue problems are not satisfactory. A model based on grain boundary cavitation and microcrack growth has been developed for better understanding. Experiments on steel P92 confirm predicted lifetimes and a creep-fatigue damage parameter, DFC, has been introduced.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Multidisciplinary
Suo Li, Jian Li, Guangai Sun, Dean Deng
Summary: In this study, a butt-welded joint between P92 ferritic steel and SUS304 austenitic stainless steel was investigated. Finite element analyses were used to study the hardness and welding residual stress. Various factors influencing the formation of hardness and residual stress were considered, and the predicted results were in good agreement with the measurements. The effects of peak temperature, internal restraint, and differential thermal expansion were found to be decisive for the formation of residual stress.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Engineering, Mechanical
Jianfeng Mao, Xiangyang Li, Dasheng Wang, Fengping Zhong, Lijia Luo, Shiyi Bao, Zhenyu Ding
Summary: This paper investigates the creep fatigue behavior of P92 steel at high temperatures through experiments and analysis, with a focus on the influence of temperature, load holding time, and pre-fatigue damage. The SEDE model is found to be the most suitable for predicting the creep fatigue life of P92 steel, while microstructure analysis and fracture morphology observations explain the damage evolution mechanism of the material.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Review
Materials Science, Multidisciplinary
Kun Zhang, Jian-Ping Tan, Wei Sun, Kamran Nikbin, Shan -Tung Tu
Summary: This article discusses the failure behavior and life prediction of engineering materials under multiaxial loading. A multiaxial stress rupture criterion (MSRC) is proposed to distinguish different failure modes, and a multiaxial factor alpha is developed to quantify the multiaxial response of material/geometry combinations. Different methods for determining MSRC are evaluated, and the use of continuum damage mechanics approaches in determining MSRC is recommended, considering the influence of creep failure mechanisms. The correlation between uniaxial material parameters and alpha is also analyzed. The study finds that the increase of uniaxial creep ductility parameter lambda is accompanied by a decrease in alpha, indicating the role of creep ductility in the multiaxial rupture behavior of materials.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Wei Zhang, Xiaowei Wang, Zitong Kang, Tianyu Zhang, Yong Jiang, Xiancheng Zhang, Jianming Gong
Summary: This study investigated the cyclic softening and remaining creep behavior of different micro-regions of P92 steel weldment using EBSD and nanoindentation. The experimental results showed that the intercritical heat-affected zone was most sensitive to CFI loading, with changes in microstructure and decreased remaining creep life as the number of fatigue cycles increased.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Materials Science, Multidisciplinary
Wei Zhang, Xuanming Zhang, Kaihao Zhang, Fei Liang, Xianxi Xia, Le Chang, Changyu Zhou
Summary: In this study, strain-controlled fatigue tests were conducted on P92 steel at 600 degrees C under uniaxial, multiaxial proportional, and multiaxial non-proportional loading conditions. The results indicate that the axial and shear stresses exhibit different responses to non-proportional loading, with proportional loading resulting in the shortest fatigue life when the strain ratio is small. The non-proportional loading induces accelerated cyclic softening in the axial direction while enhancing the shear stress.
MATERIALS CHARACTERIZATION
(2023)
Article
Engineering, Mechanical
Yuxuan Song, Yi Ma, Zhouxin Pan, Yuebing Li, Taihua Zhang, Zengliang Gao
Summary: In this study, the interaction of creep-fatigue on P92 steel welded joints was investigated through strain-controlled CF tests. It was found that CF specimens with short dwell times displayed characteristic fatigue-induced damage. The specimens subjected to CF tests showed lower hardness, elastic modulus, and creep strength compared to specimens with post-weld heat treatment, with increased strain rate sensitivities observed after secondary creep testing.
CHINESE JOURNAL OF MECHANICAL ENGINEERING
(2021)
Article
Materials Science, Multidisciplinary
Jingwei Zhang, Jie Li, Jingyi Zan, Zijian Guo, Kanglin Liu
Summary: In this paper, a constitutive model based on the creep deformation mechanism in P91 steel was established and applied to predict the creep crack growth behavior and life analysis. The accuracy and reliability of the model were verified and it can be effectively applied in the design of high-temperature structures.
Article
Mechanics
Lei Zhao, Yan Wu, Lianyong Xu, Yongdian Han
Summary: The effect of creep constraint on creep crack growth behavior and stress field around the creep crack-tip was investigated under different specimen geometry conditions. The correlation between the constraint parameters Q and Qm with stress triaxiality under creep conditions was studied. The results showed that Q and Qm depend linearly on stress triaxiality. A new load-independent constraint parameter Q*m was proposed to quantify higher out-of-plane creep constraints induced by specimen width and thickness. The constraint-dependent creep crack growth prediction model based on constraint parameters Q* and Q*m was established.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Sami Ghazali, Mohammed Algarni, Yuanli Bai
Summary: The plastic and fracture behaviors of AISI 4340 steel under multiaxial stress loading conditions were studied experimentally and numerically. A new plasticity model considering Lode angle dependence was proposed, and the model was validated by the comparison between experimental data and finite element simulations.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
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)