Article
Materials Science, Multidisciplinary
Bo Xiao, Haokai Dong, Tao Yang, Shaofei Liu, Shenbao Jin, Boxuan Cao, Yongdian Han, Lei Zhao, Xiawei Yang, Gang Sha, Lianyong Xu
Summary: We present two typical morphologies (elongated- and blocky-shaped) of the Laves phase in tempered martensite ferritic steels during creep process, which are formed through two independent paths: grain boundaries and neighboring M23C6. The presence of multi-element segregation (Cr, Mn, Si, and W) at grain boundaries and adjacent M23C6 provides a source of Laves phase formation. Additionally, different growth mechanisms play crucial roles in the formation of these two morphologies. Our findings enhance the understanding of Laves phase heterogeneous precipitation and offer insights for the development of novel heat-resistant steels with superior creep strength.
MATERIALS RESEARCH LETTERS
(2023)
Article
Chemistry, Physical
Hang Wang, Keer Li, Wei Chen, Lihong Han, Yaorong Feng
Summary: In this study, the addition of chromium element in plain carbon steel was found to effectively improve the creep resistance and remnant strength of oil casing under high temperature and high pressure conditions during in situ combustion for heavy oil recovery. The addition of 1 wt.% chromium element reduced the creep rate and maintained high remnant tensile strength, while the addition of 13 wt.% chromium element significantly enhanced the remnant strength after long-term creep. The improved mechanical performance of the chromium-doped steels is attributed to the precipitation retardation of carbides and sluggish precipitate coarsening. These findings contribute to the development of high-performance steels for unconventional petroleum and gas resources.
Article
Nanoscience & Nanotechnology
Johan Ewald Westraadt, William Edward Goosen, Aleksander Kostka, Hongcai Wang, Gunther Eggeler
Summary: The formation of modified Z-phase in a 12Cr1MoV tempered martensite ferritic steel during creep testing at high temperature and stress was investigated. The results showed that the modified Z-phase precipitated in both the uniformly-elongated gauge and thread regions of the fractured sample. Localized creep-strain strongly promoted the formation of the modified Z-phase.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
H. Wang, A. Kostka, W. E. Goosen, G. Eggeler, J. E. Westraadt
Summary: The study investigated a 12% Cr TMFS after creep testing at high temperature for 139,000 hours, using an extraction replica technique to analyze particle families and explore the chemical evolution of particles. The results were discussed in comparison with previous thin foil data and computational thermodynamics predictions, highlighting the strengths and weaknesses of thin foil and replica procedures, and suggesting improvements for thermodynamic databases.
MATERIALS CHARACTERIZATION
(2021)
Article
Materials Science, Characterization & Testing
Bhaawan Gupta, Benjamin Ducharne, Tetsuya Uchimoto, Gael Sebald, Takamichi Miyazaki, Toshiyuki Takagi
Summary: This study compared three different electromagnetic NDT techniques applied to high-chromium steels to understand the microstructural changes associated with creep evolution. Modeling techniques were proposed for each applied method, with model parameters optimized for each NDT technique and tested material. The accuracy of parameter determination strongly depends on the NDT technique, indicating its correlation with microstructural information.
NDT & E INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Salaheddine Sadi, Abdelkader Hanna, Hiba Azzeddine, Casimir Casas, Thierry Baudin, Anne-Laure Helbert, Francois Brisset, Jose Maria Cabrera
Summary: The microstructure and texture of binary Mg-0.3Ce alloy were investigated after ECAP processing at 300 and 350 degrees C. Effective grain refinement was achieved through dynamic recrystallization, with different mechanisms observed at different temperatures. Texture development varied based on strain level and DRX mechanisms, forming a typical basal texture at 300 degrees C and a different texture at 350 degrees C due to grain size.
MATERIALS CHARACTERIZATION
(2021)
Article
Chemistry, Physical
Bernd Kuhn, Michal Talik
Summary: HiperFer steels are a new type of heat-resistant, fully ferritic materials with increased mechanical strength and improved resistance to steam oxidation. Heat treatment was found to significantly improve the creep performance of the material, leading to a 100% increase in rupture time at 650 degrees C and a creep stress of 100 MPa.
Article
Materials Science, Multidisciplinary
Nicolas Di Luozzo, Sandra Cabeza, Michel Boudard, Marcelo Fontana
Summary: Transient liquid phase bonding (TLPB) welding method delivers heat simultaneously to the entire joint, resulting in lower cooling rates and lower residual stress peak magnitudes. Numerical simulation through thermal and mechanical analysis can predict residual stresses in TLPB weldments.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Amir Baghdadchi, Vahid A. Hosseini, Leif Karlsson
Summary: This study focused on phase identification and quantification in transformation induced plasticity duplex stainless steel (TDSS) base and weld metal using light optical microscopy (LOM) and electron backscatter diffraction (EBSD) analysis, with a novel methodology introduced for multiphase materials.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Nanoscience & Nanotechnology
M. Pinson, S. M. Das, H. Springer, T. Depover, K. Verbeken
Summary: The addition of 2 wt% of aluminum to a Fe-0.4 wt% C martensitic steel resulted in the formation of a ferritic microfilm along the grain boundaries. The inclusion of aluminum significantly increased the ductility of the steel.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Hongfei Wang, Chunyan Ban, Nannan Zhao, Lei Li, Qingfeng Zhu, Jianzhong Cui
Summary: In this study, pure titanium samples with a purity of 99.99 wt.% were successfully processed by ECAP at cryogenic temperature, leading to significant grain refinement and increased hardness. The activation of slip systems during deformation process was observed, and the influence of temperature on grain refinement was discussed. Factors affecting the homogeneity of microstructure were also analyzed.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Chemistry, Physical
Weiyang Wang, Shuang Zhou, Zhu Xiao, Wenting Qiu, Qian Lei
Summary: This study investigated the microstructure evolution and properties of a CuCrZrSc alloy undergoing aging treatment and equal channel angular pressing (ECAP). The results showed that pre-aging treatment significantly improved the mechanical properties and electrical conductivity of the alloy. After 12 passes of deformation and aging treatment, the alloy exhibited enhanced mechanical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Irati Zurutuza, Nerea Isasti, Eric Detemple, Volker Schwinn, Hardy Mohrbacher, Pello Uranga
Summary: The combination of boron with other microalloying elements is known to have a synergetic effect on hardenability in high-strength medium carbon steels. Different mechanisms such as solid solution hardening and fine precipitation hardening can optimize mechanical properties. Microstructural refinement is found to be most beneficial to strength and toughness, while unit size heterogeneity has a negative effect on ductile-to-brittle transition behavior. Proving that a steel with high yield strength and low impact transition temperature can be obtained by properly balancing alloy concept and processing.
Article
Nanoscience & Nanotechnology
Hao Yu, Shoukui Yang, Jianfeng Shao, David San-Martin, Wei Xu
Summary: For ferritic self-healing (FSH) steel, the low healing efficiency problem has been addressed by proposing an offline healing treatment that stimulates the formation of Laves phase precipitates as self-healing agents. The treatment extended the creep lifetime by more than 30% and reduced the creep rates by one order of magnitude. The relationship between the extended lifetime and filling ratios of creep cavities by the healing agents was established, providing a new strategy for cultivating the self-healing capabilities of heat resistant steels.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Roman Mishnev, Yuliya Borisova, Tatiana Kniaziuk, Sergey Gaidar, Rustam Kaibyshev
Summary: The effect of tempering after water quenching on the strength and fracture toughness of two steels with specific chemical compositions was studied. The precipitation of transition ?-Fe2C carbides in martensitic matrix increased fracture toughness and eliminated quench embrittlement in one of the steels. On the other hand, tempered martensite embrittlement at higher tempering temperature resulted in decreased impact energy, ductility, and strength and elongation for the other steel.
Article
Nanoscience & Nanotechnology
L. Heep, D. Burger, C. Bonnekoh, P. Wollgramm, A. Dlouhy, G. Eggeler
Summary: The low temperature high stress tensile creep behavior of the superalloy single crystal ERBO-1 was investigated, with comparisons made between loading directions of [001] and deviations towards [111] and [011]. The study found that creep rates are influenced by the loading directions, and faster creep rates are observed when dislocations from two octahedral systems experience similar driving forces.
SCRIPTA MATERIALIA
(2022)
Article
Crystallography
Pascal Thome, Mike Schneider, Victoria A. Yardley, Eric J. Payton, Gunther Eggeler
Summary: In this study, an advanced EBSD method was used to analyze the two prominent types of martensite microstructures found in the binary Fe-Ni system, lath martensite and plate martensite. By modifying, documenting, and applying an analytical EBSD procedure, high-resolution, color-coded micrographs of martensitic microstructures were obtained, which visualized the differences between lath and plate martensite and appreciated the microstructural features.
Article
Materials Science, Multidisciplinary
A. Reul, C. Lauhoff, P. Krooss, C. Somsen, D. Langenkaemper, M. J. Gutmann, B. Pedersen, M. Hofmann, W. M. Gan, I. Kireeva, Y. I. Chumlyakov, G. Eggeler, T. Niendorf, W. W. Schmahl
Summary: The martensite domain variant selection and stress-induced martensite morphology were investigated in [001]-oriented superelastic Co49Ni21Ga30 shape memory alloy single crystals under tensile load. The results showed that the precipitation of nanoprecipitates promoted the increase of habit plane interfaces and the reduction of martensite plate thickness. During tensile loading, all samples exhibited stress-induced formation of martensite, but the presence of nanoprecipitates did not necessarily promote multi-variant interaction.
Article
Materials Science, Multidisciplinary
Christian Wagner, Alberto Ferrari, Jurgen Schreuer, Jean-Philippe Couzinie, Yuji Ikeda, Fritz Koermann, Gunther Eggeler, Easo P. George, Guillaume Laplanche
Summary: The physical properties of ten single-phase FCC CrxMn20Fe20Co20Ni40-x high-entropy alloys were investigated. The lattice parameters of the alloys were nearly independent of composition, while the solidus temperatures increased linearly with increasing Cr content. The alloys did not exhibit ferromagnetism in a certain temperature range, and the temperature dependencies of their coefficients of thermal expansion and elastic moduli were independent of composition. Ab initio simulations qualitatively reproduced the magnetic transitions and magnetostriction observed in the alloys. The plastic deformation of the alloys was found to occur initially by the glide of perfect dislocations on {111} planes. The stacking fault energy (SFE) was determined and found to decrease with increasing Cr content. However, the calculated intrinsic SFEs were lower than the experimental values. The ab initio simulations showed that atomic relaxations, finite temperatures, and magnetism strongly influenced the intrinsic SFE.
Article
Materials Science, Multidisciplinary
C. Lauhoff, A. Reul, D. Langenkaemper, P. Krooss, C. Somsen, M. J. Gutmann, B. Pedersen, I. V. Kireeva, Y. I. Chumlyakov, G. Eggeler, W. W. Schmahl, T. Niendorf
Summary: This study investigates the effects of aging treatments on the martensitic transformation and functional properties of Co-Ni-Ga shape memory alloys. The formation of nanoparticles is shown to strongly influence the selection and morphology of martensite, with larger particles promoting irreversibility and smaller particles enhancing functional stability.
Article
Materials Science, Multidisciplinary
A. Kunzmann, J. Frenzel, U. Wolff, J. W. Han, L. Giebeler, D. Piorunek, M. Mittendorff, J. Scheiter, H. Reith, N. Perez, K. Nielsch, G. Eggeler, G. Schierning
Summary: Nickel-titanium (Ni50Ti50)-based alloys, as the most important shape memory alloys, have been studied to understand the role of electrons in the shape memory effect. The alloy composition affects resistivity, Hall coefficient, Seebeck coefficient, and Terahertz reflectance during the martensitic phase transformation. The charge carrier density decreases by almost one order of magnitude in the martensitic phase compared to the austenitic phase, and this reduction starts before the actual transformation. The charge carrier mobility increases during the phase transformation, indicating that additional scattering events or altered electron-phonon coupling do not play a dominant role in the electrical resistivity anomaly. The electronic entropy contribution to the phase transformation directly scales with the martensitic start temperature and can reach over 30% of the total entropy contribution for compositions close to equiatomic Ni50Ti50. Experimental data suggests a transfer of electron density from the free electron gas (austenite) to the bonding (martensite), possibly indicating the formation of a charge density wave phase.
MATERIALS TODAY PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Zhenghao Chen, Kyosuke Kishida, Haruyuki Inui, Martin Heilmaier, Uwe Glatzel, Gunther Eggeler
Summary: The effects of Ni and Ta additions on the mechanical properties of Co-based superalloys were investigated. The additions of Ni and Ta increased the yield strength at intermediate and high temperatures by increasing the stability of the L1(2) phase. The strength increase at intermediate temperatures can be attributed to the increased complex stacking fault energy and the increased anti-phase boundary energy on (111) planes. The strength increase at high temperatures is mainly due to the increased L1(2) solvus temperatures.
Article
Chemistry, Physical
A. Kostka, D. Naujoks, T. Oellers, S. Salomon, C. Somsen, E. oeztuerk, A. Savan, A. Ludwig, G. Eggeler
Summary: In this study, the process of layer growth in the Ni-Al system was investigated through experiments and observations. The results showed that a polycrystalline aluminide layer formed in the early stage of the solid-state reaction, followed by preferential grain growth in the later stage. It was also found that two different aluminide phases formed simultaneously. In-situ TEM study revealed the time dependence of layer growth rate. The findings provide insights into the growth mechanism of reaction layers and suggest areas for further research.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Johan Ewald Westraadt, William Edward Goosen, Aleksander Kostka, Hongcai Wang, Gunther Eggeler
Summary: The formation of modified Z-phase in a 12Cr1MoV tempered martensite ferritic steel during creep testing at high temperature and stress was investigated. The results showed that the modified Z-phase precipitated in both the uniformly-elongated gauge and thread regions of the fractured sample. Localized creep-strain strongly promoted the formation of the modified Z-phase.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
C. Lauhoff, T. Pham, A. Paulsen, P. Krooss, J. Frenzel, G. Eggeler, T. Niendorf
Summary: Heusler-type Co-Ni-Ga shape memory alloys have attracted attention for their excellent superelasticity in the single-crystalline state. However, polycrystalline Co-Ni-Ga suffers from premature failure at grain boundaries due to pronounced anisotropy. The study introduces a novel thermo-mechanical processing route that promotes abnormal grain growth and leads to high-performance single-crystalline structures, offering potential for direct microstructure design.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Chemistry, Physical
Daniel Gaertner, Julia Kundin, Neelamegan Esakkiraja, Jasper Berndt, Adeline Durand, Josua Kottke, Stephan Klemme, Guillaume Laplanche, Gunther Eggeler, Gerhard Wilde, Aloke Paul, Ingo Steinbach, Sergiy V. Divinski
Summary: Diffusion behavior in the CoCrFeMnNi high-entropy alloy is investigated using an augmented tracer/interdiffusion couple approach. A consistent composition-dependent diffusion database is established, and a pair-diffusion model is used to describe the tracer diffusion and chemical concentration profiles. The uphill diffusion of Co observed in the experiment cannot be explained by existing kinetic and thermodynamic databases, and the vacancy wind effect is found to have a strong influence on intrinsic cross diffusion coefficients.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Coatings & Films
Markus Kiryc, Deniz Kurumlu, Gunther Eggeler, Robert Vaben, Gabriela Marginean
Summary: This study focuses on the wear behavior of HVOF-sprayed CoNiCrAlY coatings deposited on a NiCrCoTi substrate at high temperatures. The microstructure and chemical composition of the coatings were found to significantly affect their sliding wear and solid particle erosion behavior. The formation of a thicker oxide scale on the substrate due to longer dwell times provided protective effects during sliding wear but did not benefit solid particle erosion protection.
SURFACE & COATINGS TECHNOLOGY
(2023)
Article
Chemistry, Physical
L. Pang, Z. X. Zhang, L. W. Kong, Z. B. Xing, Y. Shu, P. Li, G. Eggeler
Summary: The thermal stability of CMSX-4 nickel-based single crystal superalloy with the raft structure is studied through macro-oxidation and in-situ oxidation experiments. The oxidation morphologies on the superalloy surface include thick oxide layers with NiO and Co2O3 in the dendrite core (region A) and thin oxide layers with Al2O3, Cr-O, and TiO in the interdendrite region (region B). The migration of elements during oxidation causes changes in thickness and stress concentration between the gamma and gamma' phases, leading to voids aggregation, crack initiation, and final failure fracture.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Yuxun Jiang, Muhammad Adil Ali, Irina Roslyakova, David Buerger, Gunther Eggeler, Ingo Steinbach
Summary: A novel approach is developed to retrieve 3D information from 2D experimental micrographs using 3D phase-field simulations and artificial intelligence. The simulations are validated to reproduce microstructural features and then used to generate simulated micrographs for training a regression model. The model is then applied to experimental micrographs to retrieve hidden 3D features. This approach is applicable to metallic materials, minerals or ceramics that can be quantitatively treated by phase-field simulations.
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING
(2023)
Article
Chemistry, Physical
Pascal Thome, Mike Schneider, Victoria A. Yardley, Eric J. Payton, Gunther Eggeler
Summary: In the binary Fe-Ni system, the martensite start temperatures decrease with an increase in Ni concentrations. Alloys with Ni concentrations below 28.5 at.% exhibit lath martensite microstructures, while plate martensite forms above this concentration. A combination of ingot metallurgy, thermal analysis, and analytical orientation imaging scanning electron microscopy was used to study the microstructures and crystallographic features. The formation of transition martensite, which exhibits characteristics of both lath and plate martensite, is associated with a local maximum in the descending M-S curve.
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)
