Article
Nanoscience & Nanotechnology
Bosheng Dong, Zhiyang Wang, Zengxi Pan, Ondrej Muransky, Chen Shen, Mark Reid, Bintao Wu, Xizhang Chen, Huijun Li
Summary: The study investigated the effects of layer-remelting on high entropy alloys, revealing that it significantly degrades the tensile strength and ductility of prepared alloys. Repeated remelting of deposited material leads to thermally induced plasticity, increasing the amount of stored dislocations in the microstructure and limiting interfacial strengthening. Despite the potential strain hardening effects, the constrained dendritic morphology of BCC grains dominates and results in the loss of tensile strength.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Review
Materials Science, Multidisciplinary
Wei Zhang, Ali Chabok, Bart J. Kooi, Yutao Pei
Summary: This article summarizes the microstructure characteristics, mechanical properties, and functional properties of additive manufactured high entropy alloys (HEAs), providing a fundamental understanding of this research field. The article also discusses the current challenges and future work in this area.
MATERIALS & DESIGN
(2022)
Article
Materials Science, Multidisciplinary
Jie Ren, Margaret Wu, Chenyang Li, Shuai Guan, Jiaqi Dong, Jean-Baptiste Forien, Tianyi Li, Katherine S. Shanks, Dunji Yu, Yan Chen, Ke An, Kelvin Y. Xie, Wei Chen, Thomas Voisin, Wen Chen
Summary: We develop a dual-phase nanolamellar structure in a high-entropy alloy using laser powder-bed fusion additive manufacturing. This structure exhibits a combination of ultrahigh yield strength and large tensile ductility. The deformation mechanisms involve effective blockage of dislocation motion, stacking fault-mediated deformation, and martensitic transformation. The cooperative deformation of the dual phases, assisted by the semi-coherent lamellar interfaces, gives rise to the large ductility.
Article
Materials Science, Multidisciplinary
Zhuoheng Liang, Yongzhong Zhang, Yantao Liu, Zhengwang Zhu, Haifeng Zhang
Summary: In this study, laser melting deposition (LMD) was used to successfully form AlCoCrFeNi2.1 eutectic high-entropy alloys (EHEAs) to solve formability issues. By retaining the eutectic structure and forming a characteristic herringbone structure, the mechanical properties of the as-deposited alloy are significantly improved.
Review
Materials Science, Multidisciplinary
Ahmad Ostovari Moghaddam, Nataliya A. Shaburova, Marina N. Samodurova, Amin Abdollahzadeh, Evgeny A. Trofimov
Summary: The novel concept of high entropy alloys (HEAs) has led to the discovery of several promising materials with outstanding properties. Additive manufacturing (AM) provides new opportunities for fabricating complex HEAs and tailoring their microstructure. Future developments in HEAs are expected as the interest in AM of HEAs continues to grow.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Silja-Katharina Rittinghaus, Amr Ali, Ulrike Hecht
Summary: The medium entropy alloy AlCrFe2Ni2 was processed using Laser Direct Energy Deposition (L-DED). An intrinsic laser-based heat treatment was applied for the first time to promote phase transformation and increase the fcc phase fraction in the alloy. The microhardness remained stable during the heat treatment, offering novel possibilities for surface cladding applications.
METALS AND MATERIALS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Shunyu Liu, Corbin M. Grohol, Yung C. Shin
Summary: This paper demonstrates the effectiveness of utilizing the blown-powder additive manufacturing process, directed energy deposition (DED), for the design and synthesis of high entropy alloys (HEAs). Different microstructures of CoCrFeNiTi HEAs were successfully synthesized through a careful design of composition and particle size. The HEAs exhibited high oxidation resistance and hardness values, comparable to popular wear-resistant materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Di Ouyang, Pengcheng Zhang, Cheng Zhang, Ning Li, K. C. Chan, Lin Liu
Summary: A high-strength lamellar high-entropy alloy (HEA) of Zr45Ti31.5Nb13.5Al10 with excellent ductility was fabricated by in-situ alloying of blended elemental powders via laser directed energy deposition (DED). Microstructure characterizations suggest that the molten pools with body-centred cubic (BCC) structure and heat affected zones with mixed structure of BCC + ordered BCC (B2) nanoprecipitates, are alternately distributed in the DEDprocessed HEA with a lamellar structure. This research provides new options for the design and manufacturing of HEAs with outstanding mechanical properties for structural applications.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Nanoscience & Nanotechnology
Jian Zhang, Jikang Fan, Yong Peng, Dongqing Yang, Kehong Wang
Summary: In this study, AlCoCrFeNi2.5 eutectic high entropy alloys with nearly full relative density and no cracks were successfully fabricated by selective laser melting and annealed. The microstructures and properties of the alloys were investigated in detail. The results provide a new manufacturing processing and heat treatment method to overcome the trade-off between the strength and ductility of eutectic high entropy alloy.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Feipeng Yang, Jianying Wang, Tao Wen, Xinhai Ai, Xixi Dong, Hailin Yang, Shouxun Ji
Summary: The traditional wrought Al-Mg-Si alloys fabricated via laser powder bed fusion (LPBF) are prone to hot cracks, unless adding grain refiners in as-LPBFed Al alloys. In this work, the Al-9.6 wt.% Mg-4.9 wt.% Si alloy with low solidification range and hot-cracking susceptibility was successfully processed by LPBF. The as-LPBFed alloys have reached a high relative density of 99.3% at the VED of 129.6 J/mm(3). The microstructures were featured by fine a-Al grains and cellular eutectic Mg2Si, accompanied by a high number density of dislocations, coherent GP zone and alpha-Al-12(Fe, Mn)(3) Si phases. The as-LPBFed Al-13.3Mg(2)Si alloy exhibited the high ultimate tensile strength of 557 MPa, yield strength of 439 MPa and elongation of 2.9%. In addition to the grain refinement and dislocation strengthening, the strength enhancement is mainly ascribed to the dispersion strengthening from the divorced nanosized eutectic Mg2Si. The results demonstrate that manipulation of alloys at near eutectic composition is effective to achieve high strength Al-Mg-Si alloys processed by LPBF.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Zhen Gu, Xu Su, Wenshan Peng, Weimin Guo, Shengqi Xi, Xu Zhang, Hong Tu, Yuan Gao, Hongjing Wu
Summary: A new type of high entropy alloy, CoCr2.5FeNi2TiW0.5, was prepared by selective laser melting technology with two different protective gases, argon and nitrogen. The alloy showed higher microhardness values under nitrogen protection. This method can effectively refine grain structure and provide theoretical guidance for manufacturing fine grain materials with high strength and ductility of new HEA components.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Lin He, Shiwei Wu, Anping Dong, Haibin Tang, Dafan Du, Guoliang Zhu, Baode Sun, Wentao Yan
Summary: By leveraging the good castability of eutectic high entropy alloys and high cooling rate of selective laser melting (SLM), a nearly fully dense and crack-free AlCoCrFeNi2.1 eutectic high entropy alloy with exceptional strength-ductility synergy was obtained. The heterogeneous eutectic microstructure consisting of refined cells at nanoscale contributed to the enhanced strength and ductility.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Jingqi Zhang, Michael Bermingham, Joseph Otte, Yingang Liu, Matthew Dargusch
Summary: This study demonstrates how to achieve uniform and enhanced tensile ductility by minimizing the in-situ intrinsic heat treatment effect. By adjusting the heating and deposition time, the tensile ductility of Ti-5Al-5Mo-5V-3Cr material was successfully improved without notable variation.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Jonathan W. Pegues, Michael A. Melia, Mark A. Rodriguez, Tomas F. Babuska, Benjamin Gould, Nicolas Argibay, Aaron Greco, Andrew B. Kustas
Summary: The study utilized laser beam directed energy deposition to explore the composition space of a graded W-x(CoCrFeMnNi)(100-x) sample and found the formation of the Fe7W6 intermetallic phase and non-incorporated W particles at certain concentrations.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Manufacturing
Jia Liu, Rangasayee Kannan, Dalong Zhang, Tingkun Liu, Peeyush Nandwana, Arun Devaraj
Summary: This study investigates the microstructure-mechanical property relationships in BJ3DP H13 tool steel using atom probe tomography and transmission electron microscopy, and reports the presence of a new type of continuous eutectic film-like carbide.
ADDITIVE MANUFACTURING
(2022)
Article
Materials Science, Ceramics
Khushnuda Nur, Muhammad Zubair, James S. K-L. Gibson, Stefanie Sandloebes-Haut, Joachim Mayer, Martin Bram, Olivier Guillon
Summary: The mechanical properties of cold sintered and conventionally sintered ZnO samples were compared using nanoindentation and micro-pillar testing. It was found that cold sintered samples had higher hardness but lower elastic modulus and compressive stress. Transmission electron microscopy investigations confirmed the distinctive nature of grain boundary regions in cold sintered samples that influenced their deformation behavior.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Nanoscience & Nanotechnology
Rama Srinivas Varanasi, Marta Lipinska-Chwalek, Joachim Mayer, Baptiste Gault, Dirk Ponge
Summary: The study investigates the mechanisms of austenite growth in medium manganese steel, providing evidence of manganese transport to austenite through grain boundary diffusion, grain boundary migration, and dislocation pipe diffusion. Furthermore, the influence of grain boundary misorientation on austenite growth is also reported.
SCRIPTA MATERIALIA
(2022)
Article
Physics, Applied
Martin Mikulics, Joachim Mayer, Hilde Helen Hardtdegen
Summary: In this Perspective, possible future developments of group III-nitride nano-LEDs are introduced based on current achievements. The challenges in their fabrication and their characteristics are reported, and their applications in various fields are discussed. Advanced applications in microscopy, lithography, communication, and optical computing are highlighted. Unconventional device applications and prospects for emerging photon source-based technologies are also explored. The importance of novel device concepts in future photon source developments and their role in optical computing is emphasized.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Ke Ran, Fanlin Zeng, Liudmila Fischer, Stefan Baumann, Wilhelm A. Meulenberg, Kerstin Neuhaus, Joachim Mayer
Summary: This study characterized the newly formed phase inside dual-phase oxygen transport membranes (DP-OTMs) using advanced transmission electron microscopy techniques. The results showed that the newly formed phase is primarily surrounded by the existing phase, reducing non-solute segregation at grain boundaries. The study also observed the crystal structure of interfaces between the two phases.
Article
Materials Science, Multidisciplinary
Mostafa El Laithy, Ling Wang, Terry J. Harvey, Alexander Schwedt, Bernd Vierneusel, Joachim Mayer
Summary: Dark etching region (DER) formation is the initial stage of subsurface microstructural changes in bearing steels due to cyclic stresses, which is followed by the development of low angle bands (LAB) and high angle bands (HAB). This study analyzes the development of DER in two different steels, 100Cr6 and 50CrMo4, at different stages of bearing lifetime using SEM, EBSD, and nanoindentation. The findings show that early stages of DER are characterized by multiple dark etching bands oriented relative to the rolling direction. These bands contribute to the refinement of the parent microstructure and act as stress points that initiate LAB formation through recrystallization. This study establishes a connection between DER and LAB/HAB development in rolling bearings.
Article
Materials Science, Multidisciplinary
Ping-Luen Ho, Zhihao Huang, Lei Jin, Si-Young Choi, Rafal E. Dunin-Borkowski, Joachim Mayer, Shik Chi Edman Tsang, Xiaoyan Zhong
Summary: Aberration-corrected analytical transmission electron microscopy (TEM) is used to determine the atomic-scale cation order in a nanosized Sr3Fe2ReO9 phase, revealing tripled-layered repeats of Fe and Re cations along [111](pc) and an ordering vector of 1/3[111]*. Density functional theory calculations based on a relaxed theoretical model consistent with the experimental images determine the magnetic ground states and exchange parameters of the newly discovered Sr3Fe2ReO9 phase, where nearest-neighbour Fe and Re cations are coupled antiferromagnetically.
MICROSCOPY AND MICROANALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Lukas Voelkel, Dennis Braun, Melkamu Belete, Satender Kataria, Thorsten Wahlbrink, Ke Ran, Kevin Kistermann, Joachim Mayer, Stephan Menzel, Alwin Daus, Max C. Lemme
Summary: The switching mechanism of multilayer hexagonal boron nitride (h-BN) threshold memristors with nickel (Ni) electrodes is investigated through temperature-dependent current-voltage measurements. The formation and retraction of nickel filaments along boron defects in the h-BN film are proposed as the resistive switching mechanism. The electrical data are corroborated with TEM analyses, confirming the viability of using temperature-dependent current-voltage measurements as a valuable tool for analyzing resistive switching phenomena in memristors made of 2D materials. The memristors exhibit wide current operation range, low standby currents, low cycle-to-cycle variability, and a large On/Off ratio.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Joachim Pasel, Johannes Haeusler, Dirk Schmitt, Helen Valencia, Joachim Mayer, Ralf Peters
Summary: The catalytic upgrading of CO2-based ethanol into valuable products, such as higher alcohols, is an increasingly popular research topic. Among these products, carbon-neutral n-butanol has the potential to replace a significant portion of conventional gasoline in the transportation sector. The Guerbet reaction, particularly the homo aldol condensation of acetaldehyde, has been studied as a promising synthesis route for n-butanol. In this study, the Temporal Analysis of Products methodology was used to investigate the reaction, with lanthanide oxides supported on activated carbon as catalysts. The research revealed the formation of butanol through the aldol condensation of acetaldehyde, as well as its decomposition into CO, CH4, and H2. Carbonaceous deposits were formed when acetaldehyde was pulsed onto the catalyst surface, but catalyst regeneration was successfully achieved through O2 pulsing. Other reaction routes leading to acidic acid, ethyl acetate, or diethyl ether were excluded through experimental tests.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Environmental Sciences
Aida M. Diez, Marta Pazos, M. Angeles Sanroman, Helen Valencia Naranjo, Joachim Mayer, Yury Kolen'ko
Summary: This study successfully synthesized and characterized fluoride-doped-TiO2 and demonstrated its applicability in solid-phase photodegradation of polyethylene films for the first time. After three weeks of UV A radiation using a low consumption LED lamp, the polyethylene films containing only 2% of the photocatalyst experienced nearly 50% weight loss, surpassing previously reported data. The results suggest the potential for future production of self-photodegradable plastics for environmental and wastewater treatment applications.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Materials Science, Multidisciplinary
Michael Frentzen, Michail Michailow, Ke Ran, Noel Wilck, Joachim Mayer, Sean C. Smith, Dirk Koenig, Joachim Knoch
Summary: Recently, the nanoscale electronic structure shift induced by anions at surfaces (NESSIAS) has been described, based on density functional theory calculations and experimental data. This model explains the structure shift of low-doped single-crystalline Si nanowells (Si-NWs) with thicknesses <= 3 nm embedded in SiO2 (Si3N4) towards n-type (p-type) behavior. The influence of anions allows for very steep p-n junctions without the drawbacks of impurity doping. The process to fabricate crystalline silicon (c-Si) NWs embedded in SiO2 and Si3N4 is described and evaluated in terms of reproducibility and surface roughness.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Sankaran Shanmugam, Martin Peterlechner, Mohamad Riza Iskandar, Ujjal Saikia, Vladislav Kulitckii, Marta Lipinska-Chwalek, Joachim Mayer, Harald Roesner, Tilmann Hickel, Sergiy Divinski, Gerhard Wilde
Summary: Al3(Sc,Zr,Ti) nanoparticles with an ideal twin-type orientation relationship to Al host matrix were observed in cold-rolled and annealed Al-based alloy. High-resolution scanning transmission electron microscopy showed coherent (111) twin-type interfaces along their longer facets and semi-coherent twin interfaces on their shorter facets. Ab-initio calculations supported the formation of a coherent Al/Al3Sc twin-like phase boundary as a local energy minimum.
SCRIPTA MATERIALIA
(2023)
Article
Polymer Science
Daniel T. Krause, Susanna Kraemer, Vassilios Siozios, Andreas J. Butzelaar, Martin Dulle, Beate Foerster, Patrick Theato, Joachim Mayer, Martin Winter, Stephan Foerster, Hans-Dieter Wiemhoefer, Mariano Gruenebaum
Summary: Poly(ethylene oxide) block copolymers (PEOz BCP) have been found to have high lithium ion (Li+) conductivity and can be used in Li+ batteries. A synthetic method has been developed to independently vary the block lengths of the polymer while keeping the PEOz block length constant, allowing for a systematic exploration of the influence of block lengths on ion conductivity.
Article
Chemistry, Physical
Eugen Seif, Joachim Roesler, Jonas Werner, Thomas E. Weirich, Joachim Mayer
Summary: Cobalt-Rhenium (Co-Re) based alloys are potential high-temperature materials with adjustable melting temperatures through varying the rhenium (Re) content. Particle strengthening with tantalum carbide (TaC) and titanium carbide (TiC) showed promising results for these alloys.
Review
Chemistry, Physical
Shibabrata Basak, Krzysztof Dzieciol, Yasin Emre Durmus, Hermann Tempel, Hans Kungl, Chandramohan George, Joachim Mayer, Ruediger-A. Eichel
Summary: In this review, recent developments in battery materials and electrochemistry revealed by in situ transmission electron microscopy (TEM) are highlighted. Studying battery electrode processes is crucial for further advancements in battery technologies, and the integration of in situ/operando TEM methodologies with correlation microscopy tools can provide valuable information on battery interface evolution, reactivity, and stability, contributing to the optimization of real-world batteries.
CHEMICAL PHYSICS REVIEWS
(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)
