Article
Multidisciplinary Sciences
Shufen Chu, Pan Liu, Yin Zhang, Xiaodong Wang, Shuangxi Song, Ting Zhu, Ze Zhang, Xiaodong Han, Baode Sun, Mingwei Chen
Summary: In this study, the authors report real-time atomic-scale observations of grain boundary dislocation climb in nanostructured gold at room temperature. The climb of a dislocation is found to occur through stress-induced reconstruction of neighboring atomic columns. The proposed atomic route of dislocation climb is energetically favorable, as demonstrated by Monte Carlo simulations. The in situ observations also reveal the significance of grain boundary dislocation climb in controlling the microstructures and properties of nanostructured metals.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Karl-Fredrik Nilsson, Daniele Baraldi, Stefan Holmstrom, Igor Simonovski
Summary: This paper presents a finite element analysis of the small punch creep test for 316L(N) and compares it with experimental data. The results show good agreement between computed and experimental values, with conclusions drawn related to the friction coefficient.
Article
Geochemistry & Geophysics
Peiyang Yu, Peng-Zhi Pan, Guangliang Feng, Zhaofeng Wang, Shuting Miao
Summary: Understanding the time-dependent characteristics of Beishan granite after excavation is crucial for ensuring the long-term stability and disaster control of the high-level radioactive waste repository. Experimental results show that the unloading path significantly affects the instantaneous volume deformation, but has minor effects on creep strain. The axial and lateral creep strain are mainly determined by creep fracture potential, which can be evaluated using a unified time-dependent fracture potential index. A damage mechanical model based on time-dependent subcritical crack growth theory reveals that strain hardening dominates the granite creep process and the strain softening effect is enhanced with increasing fracture potential index.
Review
Engineering, Mechanical
Mohsin Sattar, A. R. Othman, S. Kamaruddin, Maaz Akhtar, Rashid Khan
Summary: This study presents a review of five established models for creep prediction, analyzing their significance and limitations. It explains creep phenomenon and mechanism, and provides a historical overview of the models. Through case studies, the pros and cons of using the models are highlighted, and comparisons are made among them. This review paper serves as a reliable reference for the selection of creep prediction models.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Electrochemistry
Yunlong Wu, Sui Yuan, Jiayin Yan, Jiajun Liu, Jing Nong, Qi Guo, Jian Xu
Summary: The study utilized a solution with a NaOH concentration higher than 7 mol l(-1) to dissolve Laves phase precipitates in ASTM A335 P92 steel, and the amount of precipitates was obtained by potentiodynamically polarizing the sample and integrating the dissolution current over time. Results showed a good linear correlation between this method and traditional SEM observation, and the dissolution mechanism was discussed based on the electrochemical behavior of different materials in the strong alkaline solution.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Materials Science, Multidisciplinary
Osman Mamun, Madison Wenzlick, Arun Sathanur, Jeffrey Hawk, Ram Devanathan
Summary: In this study, a direct rupture life parameterization using a gradient boosting algorithm was shown to effectively train machine learning models for highly accurate prediction of rupture life in various alloys. The Shapley value was utilized to quantify feature importance, making the model interpretable by identifying the impact of different features on performance. Additionally, a generative model based on a variational autoencoder was used to sample hypothetical synthetic candidate alloys from the learned joint distribution.
NPJ MATERIALS DEGRADATION
(2021)
Article
Materials Science, Multidisciplinary
Zhifang Peng, Sheng Liu, Chao Yang, Huachun Yang
Summary: This study analyzed the correlation between hardness and creep-rupture properties to determine the hardness values that satisfy the maximum allowable stress requirements at elevated temperatures according to ASME BPVC. The study found that a lower limit of 205HBW is suitable for different materials and components at different temperatures.
MATERIALS AT HIGH TEMPERATURES
(2022)
Article
Materials Science, Multidisciplinary
K. Kimura, K. Sawada
Summary: The creep rupture ductility of both creep strength-enhanced ferritic steels and conventional 2.25Cr-1Mo steels was investigated. A trade-off relation between creep rupture strength and creep rupture ductility was found for Grade T/P23 steels, as well as for conventional 2.25Cr-1Mo steels. The decrease in creep rupture ductility and strength was attributed to microstructural changes caused by inhomogeneous recovery of tempered martensitic microstructure. A modified heat treatment process with intermediate tempering was found to improve the creep rupture ductility of Grade P92 steel by reducing residual stress.
MATERIALS AT HIGH TEMPERATURES
(2022)
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
Nanoscience & Nanotechnology
Yue Wang, Li Shi, Chaoyu Han, Kejian Li, Zhipeng Cai, Haitao Wang
Summary: The study systematically investigated the creep rupture mechanisms of IN617 by establishing the relationship between microstructural characteristics and creep performance. Different rupture mechanisms were identified under various conditions, such as sliding and migration of recrystallized grain boundaries, creep voids along the grain boundaries, and microstructural degradation and internal oxidization, which ultimately accelerated creep rupture.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Injin Sah, Jong-Bae Hwang, Eung-Seon Kim
Summary: The study focused on the manufacturing and evaluation of a diffusion weldment for plate-type heat exchangers in the next-generation nuclear industry. Microscopic analysis showed the formation of Al-rich oxides along the interface, hindering grain-boundary movement and resulting in premature brittle fracture. Despite lower performance compared to the original alloy, the diffusion weldment exhibited some stability under high stress conditions.
Article
Green & Sustainable Science & Technology
Ruihong Wang, Hao Luo, Chao Yang, Fang Wang
Summary: This study conducted creep tests and stress relaxation tests on mud-calcareous conglomerates from the Three Gorges Reservoir Area, and determined the long-term strength values of the conglomerate specimens via different methods based on the test curves. By comparing these mainstream long-term strength determination methods, each was found to have its own drawbacks. Therefore, a new method called the steady-state creep rate method was proposed, which showed good agreement with other established methods.
Article
Construction & Building Technology
Benjamin Shannon, Guoyang Fu, Rukshan Azoor, Ravin Deo, Jayantha Kodikara
Summary: Rehabilitation of water pipe infrastructure is crucial to reduce costs and water loss. Cured-in-place pipe (CIPP) liners are a method of rehabilitation, and this paper investigates the long-term properties of CIPP liners. The study finds that the creep retention factor is not a reliable estimate of rupture strength or fatigue strength reduction.
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2022)
Article
Chemistry, Physical
Liming Xu, Yinsheng He, Yeonkwan Kang, Jine-sung Jung, Keesam Shin
Summary: This study investigates the precipitation evolution in HR3C steel at elevated temperatures of 700 degrees C and 750 degrees C. The main precipitates observed during creep exposure are Z-phase, M23C6, and r phase. Z-phase precipitates dispersedly in the austenite matrix along dislocation lines, while M23C6 preferentially precipitates at grain boundaries. Additionally, a brittle sigma phase is formed during long-term creep at high temperatures.
Article
Mechanics
Tara Habibi, Landolf Rhode-Barbarigos, Thomas Keller
Summary: This study explores the application limits of composites for permanent large-scale bending-active structures by systematically evaluating the effects of influential geometrical and material parameters. The results demonstrate that increasing material stiffness and creep-rupture stress limit can further enhance the span, applicable live load, and material use.
COMPOSITE STRUCTURES
(2022)
Article
Multidisciplinary Sciences
Ferenc Kun, Gergo Pal, Imre Varga, Ian G. Main
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2019)
Article
Multidisciplinary Sciences
Viktoria Kadar, Gergo Pal, Ferenc Kun
SCIENTIFIC REPORTS
(2020)
Article
Multidisciplinary Sciences
Gabor Domokos, Douglas J. Jerolmack, Ferenc Kun, Janos Torok
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Physics, Multidisciplinary
Zoltan Halasz, Imre Kallai, Ferenc Kun
Summary: In this study, an extension of fiber bundle models was proposed to describe the mechanical response of systems undergoing stick-slip cycles, considering changing stiffness and fluctuating slip events. Analytic expressions for the constitutive response of the bundle were derived under the assumption of global load sharing, showing plastic behavior on the macro-scale. The research found that the macroscopic response of hardening bundles is more sensitive to fluctuations in the number of stick-slip cycles allowed.
FRONTIERS IN PHYSICS
(2021)
Article
Multidisciplinary Sciences
Gergo Pal, Gabor Domokos, Ferenc Kun
Summary: The passage discusses the impact-induced attrition processes in industrial ore processing and their role in determining the origin of sedimentary particles. It establishes a connection between microscopic particle-based models and mean field theory for these processes. By conducting realistic computer simulations, the study identifies the damage and fragmentation energy phases, showing that the former consists of abrasion and cleavage phases, linking shape evolution with spatio-temporal patterns.
SCIENTIFIC REPORTS
(2021)
Editorial Material
Physics, Multidisciplinary
Alex Hansen, Ferenc Kun, Srutarshi Pradhan, Purusattam Ray
FRONTIERS IN PHYSICS
(2021)
Article
Mathematics, Interdisciplinary Applications
Attia Batool, Gergo Pal, Zsuzsa Danku, Ferenc Kun
Summary: We studied the failure process of fiber bundles on complex networks and focused on the effect of the degree of disorder of fibers' strength on the transition from localized to mean field behavior. We found that the degree of strength disorder of network nodes has a substantial effect on the transition, which occurs at a finite rewiring probability and increases as the degree of disorder decreases.
CHAOS SOLITONS & FRACTALS
(2022)
Article
Physics, Multidisciplinary
Viktoria Kadar, Zsuzsa Danku, Gergo Pal, Ferenc Kun
Summary: We investigated the impact of competition between disordered local strength and evolving inhomogeneous stress field on the evolution of breaking avalanches during the fracture of heterogeneous materials. Using a fiber bundle model, we found that an acceleration of the fracture process occurs in a region of the parameter space of strength disorder, which is shorter compared to a homogeneous stress field due to increased brittleness caused by stress localization.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2022)
Article
Mathematics, Applied
Attia Batool, Zsuzsa Danku, Gergo Pal, Ferenc Kun
Summary: The study investigates the influence of the topology of load transmitting connections and the disorder of element strength on the temporal evolution of failure cascades. It found that with increasing rewiring probability, the bundle transitions from localized to mean field breakdown phenomena, and the size and duration of failure cascades follow power law distribution with a crossover between different exponents.
Article
Chemistry, Physical
Roland Szatmari, Zoltan Halasz, Akio Nakahara, So Kitsunezaki, Ferenc Kun
Summary: The study reveals that crack initiation and propagation can be determined by the microstructure of the material, and when the anisotropy strength is sufficiently high, cracking evolves through specific stages of alignment, secondary cracking, and binary fragmentation, resulting in a connected crack network.
Article
Physics, Fluids & Plasmas
Attia Batool, Gergo Pal, Ferenc Kun
Article
Physics, Fluids & Plasmas
Viktoria Kadar, Ferenc Kun
Article
Physics, Fluids & Plasmas
Zsuzsa Danku, Geza Odor, Ferenc Kun
Article
Physics, Fluids & Plasmas
Reka Korei, Ferenc Kun
Article
Physics, Fluids & Plasmas
Zoltan Halasz, Akio Nakahara, So Kitsunezaki, Ferenc Kun