Article
Metallurgy & Metallurgical Engineering
Yaqiang Li, Yang He, Jianhua Liu, Zhenqiang Deng, Shengtao Qiu, Pei Zhang, Guiyun Zheng
Summary: In this study, CCT diagrams of undeformed and deformed pearlite heat-resistant steels were compared and analyzed. The results show that austenite deformation extends the ferrite and pearlite transformation fields, increases the critical cooling rates for achieving ferrite and pearlite microstructures, and suppresses the transformation of bainite and martensite. Additionally, it reduces the hardness of the tested steel at the same cooling rate and ferrite grain size at lower cooling rates.
IRONMAKING & STEELMAKING
(2021)
Article
Chemistry, Physical
Emad Maawad, Andreas Stark
Summary: TIMETAL (R) 54M is a relatively new (alpha + beta) Ti alloy with better machinability and forgeability compared to Ti-6Al-4V. Through in situ measurements using high energy synchrotron X-ray diffraction (HE-XRD) and a dilatometer setup, it was found that the temperature range of beta ->alpha phase transformation of Ti-54M during cooling at higher rates is larger than that of Ti-6Al-4V, resulting in different CCT diagrams.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Thermodynamics
R. F. M. Santos, V. P. Ricci, C. R. M. Afonso
Summary: This study aims to obtain continuous cooling transformation (CCT) diagrams for metastable beta Ti-12Mo-6Zr-2Fe (TMZF) and stable beta Ti-40Nb alloys and analyze their microstructure, elastic modulus, and Vickers microhardness under varied cooling rates. The results show that with an increase in cooling rate, both alloys exhibit lower Vickers microhardness and elastic modulus values.
THERMOCHIMICA ACTA
(2022)
Article
Materials Science, Multidisciplinary
G. Mandal, I. Dey, S. Mukherjee, S. K. Ghosh
Summary: This study investigates the phase transformation mechanical behavior of newly developed ultrahigh strength steels, focusing on the bainitic and martensitic phase transformations and their transformation temperature range and microstructural evidences. The study finds a strong dependency of microstructure and mechanical properties on cooling rate, and the investigated steels exhibit ultrahigh strength and reasonable ductility, attributed to their mixed microstructure and fine precipitates.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Materials Science, Multidisciplinary
Ying Dong, Zhen Tao, Chao Sun, Hongyan Wu, Xiuhua Gao, Linxiu Du
Summary: The continuous cooling transformation of deformed austenite and its relationship to mechanical properties in medium-Mn steel was studied through thermomechanical controlled processing and continuous cooling processes. The addition of manganese significantly improved the stability of austenite, and martensite transformation only occurred during slow furnace cooling. The microstructure of the experimental steel was composed of lath martensite and a small amount of retained austenite. With decreasing rolling temperature, the morphology of prior austenite grains changed from equiaxed recrystallization type to flat-elongated type, resulting in refined martensitic laths due to the fragmentation of prior austenite grains and strain hardening introduced by hot rolling.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Xin Li, Qisong Zhu, Sinong Liu, Changliang Wang, Feng Li, Fuwen Chen, Liang Feng, Hui Wang, Jialin Cheng, Hui Chang
Summary: The phase transformation and mechanical properties of Ti6Al4V-0.55Fe alloy were investigated. It was found that beta ->alpha phase transformation is a nucleation-growth-controlled process. The thickness of alpha phase lamellar decreased, while the strength and hardness increased with the increasing cooling rate. However, the plasticity of the alloy will decrease under higher cooling rates.
MATERIALS SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Physical
Zitong Gao, Rui Hu, Zijing Huang, Yulun Wu, Jinguang Li, Mi Zhou
Summary: This study investigates the metastable transformation behavior in a cast Ti-48Al-3Nb1.5Ta alloy during continuous cooling. The results show that a small amount of Ta promotes metastable transformations and reduces the cooling rates required. Crystallographic and kinetics studies reveal the nucleation mechanism of the Widmanstatten transformation. Thermodynamic analyses suggest that Ta may reduce the energy of the gamma phase boundaries to promote the nucleation of metastable structures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Zhenqiang Wang, Dongshen Huo, Yanyuan Zhou, Guoying Sui, Fengchun Jiang
Summary: The addition of tungsten has significant effects on the CCT characteristics and phase transformation behavior of high titanium microalloyed steel. It shifts the transformation products to the right side of the CCT diagram, influences the ferrite and bainite phase transformations, and enhances the particle size refinement and number density of precipitates.
Article
Nanoscience & Nanotechnology
Dan Chen, Zhenqiang Wang, Yang Zhang, Hongkai Lian, Yongxuan Shang, Mingyu Fan, Lu Dai, Lixin Sun, Ye Cui, Zhongwu Zhang
Summary: The effects of high temperature deformation on the microstructure and mechanical properties of a low carbon bainitic ferrite steel were investigated. It was found that high temperature deformation changes the microstructure and decreases the hardness of the steel. Additionally, increasing the cooling rate leads to higher yield and tensile strength, but has minor effects on impact energy value.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Mathematics, Applied
Vaclav Kotlan, Iveta Petrasova, Ivo Dolezel
Summary: This paper discusses the use of standard continuous cooling transform (CCT) diagrams for determining the hardness of surfaces obtained through laser or small-size induction hardening. Misuse of these diagrams may result in discrepancies between model values and experimental data, due to the different heat transfer mechanisms involved. The paper proposes a methodology combining theoretical and experimental approaches to mitigate errors, and provides an example to illustrate the effectiveness of the methodology. (c) 2023 Elsevier B.V. All rights reserved.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(2023)
Article
Metallurgy & Metallurgical Engineering
M. Krbata, J. Majerik, I. Barenyi, M. Eckert, R. Cep, J. Sedlak, I. Samardzic
Summary: The article presents the results of investigations on the phase transformations of tool steel X155CrMoV12. The obtained experimental data was used to evaluate the Continuous Cooling Transform (CCT) diagram and the microstructure and hardness for different heat treatment modes were characterized. Atomic Force Microscopy (AFM) was used to study the carbides in the steels and their size and shape for different cooling modes.
Article
Materials Science, Multidisciplinary
Monica Aline Magalhaes Gurgel, Eustaquio de Souza Baeta Junior, Rodolfo da Silva Teixeira, Gabriel Onofre do Nascimento, Suzane Sant'Ana Oliveira, Duilio Norberto Ferronatto Leite, Luciano Pessanha Moreira, Luiz Paulo Brandao, Andersan dos Santos Paula
Summary: Reducing pollutant emissions and improving safety standards are primary targets for modern mobility improvement. To meet these needs, the development of low-density steels containing aluminum is a new frontier of research for automotive applications. This study evaluates the phase transformations of a high aluminum content and niobium addition alloy belonging to the Fe-Mn-Al-C system. Dilatometry tests were conducted to obtain a transformation diagram, which will facilitate future processing.
Article
Materials Science, Multidisciplinary
Mats Hogstrom, Amirhosein Fadaei, Amin Rahimi, Peigang Li, Mattias Igestrand, Joel Andersson, Americo Scotti
Summary: This study aims to propose a methodology for constructing MC-CCT (Multiple Cycle Continuous Cooling Transformation) diagrams for Wire Arc Additive Manufacturing (WAAM) by combining physical and numerical simulations. Physical simulations were conducted to replicate the typical thermal cycles in additive manufacturing, and the resulting microstructures and hardness were characterized. Numerical simulations were used to determine the shape of the transformation curves, and the final CCT diagram was estimated by matching the experimental results with the numerical simulation curves.
Article
Metallurgy & Metallurgical Engineering
Kohichi Isobe, Yuga Kumagai, Takumi Satou
Summary: To optimize the reverse transformation treatment for preventing hot rolling cracking, three-dimensional metallo-thermo-mechanical analyses were performed. The analyses investigated the effects of nonuniform cooling and gamma grain size on thermal deformation and stress generation during cooling. It was found that the cooling time and type of transformation greatly affect the bloom deformation behavior during cooling, and there is a difference in stress generation mechanism depending on the type of transformation that occurs.
ISIJ INTERNATIONAL
(2023)
Article
Metallurgy & Metallurgical Engineering
Zhixiang Fu, Gengwei Yang, Yaowen Xu, Ruyang Han, Qilong Yin, Siqian Bao, Gang Zhao
Summary: The CCT diagram of 30CrMo steel simulated by compact strip production process was constructed, and the impact of austenite deformation on CCT behavior was investigated. With increasing cooling rate, the microstructure transformed from proeutectoid ferrite and pearlite to bainite and martensite, leading to refined microstructure and increased hardness. Austenite deformation strongly promoted proeutectoid ferrite formation at lower cooling rates, while inhibiting martensite transformation at higher cooling rates.
IRONMAKING & STEELMAKING
(2021)
Article
Materials Science, Multidisciplinary
Daeyoung Kim, Hansol Maeng, Young Choi, Hyunjoo Choi, Seok-Jae Lee
Summary: The study proposed a constitutive model to predict the tensile behavior of Al-Mg-Si alloy based on the characteristics of aging precipitates, and demonstrated the impact of various precipitates on strength through different aging treatments.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Seunggyu Choi, Junhyub Jeon, Namhyuk Seo, Seung Bae Son, Seok-Jae Lee
Summary: This study investigated the effects of heating rate during solid solution heat treatment on the mechanical properties and microstructure of 7055 aluminum alloy. Dilatometric tests were conducted to control the heating rates, and a variety of methods were used to evaluate mechanical properties and microstructural features. Characteristics of precipitates for each heating rate were calculated through thermodynamic simulation, and a model for predicting mechanical properties was proposed based on the results.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Junhyub Jeon, Gwanghun Kim, Namhyuk Seo, Hyunjoo Choi, Hwi-Jun Kim, Min-Ha Lee, Hyun-Kyu Lim, Seung Bae Son, Seok-Jae Lee
Summary: Ni-based amorphous alloys have unique physical properties and are attracting attention in biomass plants. Machine learning algorithms are used to design and predict the thermal properties of these alloys, with a focus on determining the optimal composition.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Nanoscience & Nanotechnology
Hyun Wook Lee, Tak Min Park, Namhyuk Seo, Seok-Jae Lee, Changmin Lee, Jeongho Han
Summary: This study aimed to develop cost-effective steels for cryogenic applications by investigating the microstructural evolutions and impact absorbed energy of a newly designed Fe-2Mn-5Ni-0.1C steel treated with quenching-tempering (QT) and quenching-lamellarizing-tempering (QLT) processes. The QLT-processed steel exhibited a higher impact absorbed energy than the QT-processed steel and Fe-9Ni steel at -196 degrees C, thanks to the active transformation-induced plasticity from retained austenite and pronounced plastic deformation of the soft martensitic matrix due to double-step tempering.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Junhyub Jeon, Namhyuk Seo, Seung Bae Son, Jae-Gil Jung, Seok-Jae Lee
Summary: This study accurately predicts the carbon diffusivity in steels using machine learning methods and provides specific insights into the prediction mechanisms of features.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Junhyub Jeon, DongEung Kim, Jun-Ho Hong, Hwi-Jun Kim, Seok-Jae Lee
Summary: We investigated various numerical methods to predict the hardness of tempered martensite in low alloy steels, including physical-based empirical equation, linear regression, shallow neural network, and deep learning approaches. We found that the physical-based empirical equation and the regression model based on the response surface method had similar prediction accuracy. The prediction accuracy of the machine learning models improved with increased complexity, but overfitting became a concern. Interestingly, a single layered neural network model with optimized hyperparameters showed similar or better hardness prediction performance compared to deep learning models with more complex architectures.
KOREAN JOURNAL OF METALS AND MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Junhyub Jeon, Namhyuk Seo, Jae -Gil Jung, Seung Bae Son, Seok-Jae Lee
Summary: This paper presents a machine learning model for predicting the Acm temperature in the Fe-C phase diagram. The dataset is analyzed and adjusted, and the model is verified and analyzed using various techniques such as cross-validation and Shapley additive explanations.
MATERIALS TRANSACTIONS
(2022)
Article
Materials Science, Multidisciplinary
Jungjoon Kim, Dongchan Min, Suwon Park, Junhyub Jeon, Seok-Jae Lee, Youngkyun Kim, Hwi-Jun Kim, Youngjin Kim, Hyunjoo Choi
Summary: Densification of amorphous powder is crucial for energy-conversion parts. Mixing powders of different sizes enhances densification. Analytical model and computational simulation were used to predict powder packing behavior, and a machine learning model achieved high packing fraction.
MATERIALS TRANSACTIONS
(2022)
Article
Materials Science, Multidisciplinary
Junhyub Jeon, Namhyuk Seo, Jae-Gil Jung, Hee-Soo Kim, Seung Bae Son, Seok-Jae Lee
Summary: In this study, a machine-learning model is used to predict austenite-grain growth, and explainable artificial intelligence (XAI) is applied to analyze the variable importance and mechanisms. With a large amount of collected data and the elimination of outliers using statistical methods, random forest regression (RFR) is selected as the model. The results show an improvement in the accuracy of the machine-learning model.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Nanoscience & Nanotechnology
Jungbin Park, Junhyub Jeon, Namhyuk Seo, Singon Kang, Seung Bae Son, Seok-Jae Lee, Jae-Gil Jung
Summary: The evolution of microstructure and mechanical properties of AISI 4340 steel during high-energy ball milling, spark plasma sintering (SPS), and post heat treatments was investigated. The study found that high-energy ball milling resulted in the formation of a nanocrystalline (-10 nm) bcc Fe matrix with segregation of alloying elements and oxide particles. The as-sintered alloy consisted of martensite-austenite (MA) constituent and fine pearlite, while the quenching after austenitization formed a microstructure composed of martensite and MA constituent. Tempering induced the decomposition of retained austenite and precipitation of cementite particles. The compressive yield strength of the as-sintered alloy was primarily strengthened by dislocations and grain boundaries/cementite lamellae, as well as secondary strengthening by oxide particles.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Metallurgy & Metallurgical Engineering
Gwanghun Kim, Jungbin Park, Seok-jae Lee, Hee-soo Kim
Summary: Cu-Sn alloys, known as bronze, have been widely used for various purposes since ancient times. This study focuses on the Cu-22Sn alloy with a higher tin content than traditional bronze, which is difficult to manufacture by conventional casting methods due to the carbon solubility of copper and tin. Cu-22Sn-xC alloy was successfully fabricated using mechanical alloying and spark plasma sintering, and its microstructural characteristics were analyzed. The hardness of sintered Cu-22Sn-xC alloy was compared with Cu-22Sn alloys manufactured by rolling, casting, and forging, and B0 sintered alloy showed the highest hardness.
ARCHIVES OF METALLURGY AND MATERIALS
(2023)
Article
Metallurgy & Metallurgical Engineering
Jungbin Park, Jonghyun Jeon, Namhyuk Seo, Gwanghun Kim, Seung Bae Son, Jae-Gil Jung, Seok-Jae Lee
Summary: The stability of austenite and the strain-induced martensitic transformation behavior of a nanocrystalline FeNiCrMoC alloy were studied. The alloy was prepared by high-energy ball milling and spark plasma sintering. X-ray diffraction was used to measure the phase fraction and grain size. The grain sizes of the milled powder and sintered alloy were found to be in the nanometer range. The variation in austenite fraction during compressive deformation was measured, and the austenite stability and strain-induced martensitic transformation behavior were calculated. Hardness measurements were performed to assess the mechanical properties, and the hardness increased to 64.03 HRC when compressed up to 30%.
ARCHIVES OF METALLURGY AND MATERIALS
(2023)
Article
Metallurgy & Metallurgical Engineering
Seong-Min So, Ki-Yeon Kim, Il -Song Park, Seok-Jae Lee, Dong-Jin Yoo, Yeon-Won Kim, Min -Suk Oh
Summary: A Si-Fe-Al ternary oxide-based micropowder coating was applied to prevent the formation of Zn coating on steel during hot-dip galvanizing process, reducing welding fume and defects in Zn-galvanized steel welding. The optimized oxide coating remained stable at 470 degrees C and effectively inhibited Zn coating formation. Residual Zn could be easily removed mechanically. This coating reduced Zn fume and prevented Zn from melting in weld bead during high-temperature welding, thereby reducing welding defects. The study showed that this pretreatment simplifies manufacturing process and saves time cost-effectively.
ARCHIVES OF METALLURGY AND MATERIALS
(2023)
Article
Metallurgy & Metallurgical Engineering
Min Woo Lee, Young Sin Choi, Do Hun Kwon, Eun Ji Cha, Hee Bok Kang, Jae In Jeong, Seok Jae Lee, Hwi Jun Kim
Summary: In this study, artificial intelligence and machine learning were used to optimize the amount of metalloid elements added to a Fe-based amorphous alloy to enhance its soft magnetic properties. The effects of metalloid elements on magnetic properties, such as saturation magnetization and coercivity, were investigated through correlation analysis. Regression analysis using the Random Forest Algorithm was performed, and the coefficient of determination was found to be 0.95. Furthermore, when considering the phase information of the Fe-Si-B-P ribbon, the coefficient of determination increased to 0.98. The optimal range of metalloid addition was predicted using correlation analysis and machine learning.
ARCHIVES OF METALLURGY AND MATERIALS
(2022)
Article
Metallurgy & Metallurgical Engineering
Young-sin Choi, Do-hun Kwon, Min-woo Lee, Eun-ji Cha, Junhyup Jeon, Seok-jae Lee, Jongryoul Kim, Hwi-jun Kim
Summary: The soft magnetic properties of Fe-based amorphous alloys can be controlled through alloy design, but there is a discrepancy between experimental data and predicted values. Machine learning processes can be used to optimize the composition for further improvement of the soft magnetic properties.
ARCHIVES OF METALLURGY AND MATERIALS
(2022)
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)
