Article
Engineering, Manufacturing
Yaowen Wu, Xinyi Zhao, Qiang Chen, Can Yang, Mingguang Jiang, Changyong Liu, Zhe Jia, Zhangwei Chen, Tao Yang, Zhiyuan Liu
Summary: A precipitation hardening high-entropy alloy (HEA) (FeCoNi)(86)Al7Ti7 fabricated by selective laser melting (SLM) and aging treatment showed significantly increased yield strength due to the coherent precipitates. Furthermore, the ductility decreased with the volume fraction of incoherent precipitates. Additionally, a new fracture mode, intercellular fracture, was proposed and validated through microstructural examination.
VIRTUAL AND PHYSICAL PROTOTYPING
(2022)
Article
Nanoscience & Nanotechnology
Xicong Ye, Zihao Cheng, Chang Liu, Xin Wu, Luer Yu, Mengyu Liu, Dong Fang, Guangwei Zhao, Bo Li
Summary: The emergence of eutectic high entropy alloys (EHEAs) has led to the design and preparation of a set of low-cost Co-free Fe55Cr15Ni(30-x)Nbx (x = 0, 3, 6, 9, 12, and 15 at.%) EHEAs in this study. The addition of Nb content affects the solidification structure and mechanical properties of the alloys.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Biliang Yuan, Chuanqiang Li, Yong Dong, Yang Yang, Peng Zhang, Zhengrong Zhang
Summary: The as-printed Al0.3CoCrFeNiCu high-entropy alloy (HEA) was successfully fabricated using selective laser melting (SLM) technology. The SLM-processed HEA exhibited a simple disordered face centered cubic solid solution with excellent mechanical properties. However, the presence of defects in the SLM alloy limits its application.
MATERIALS & DESIGN
(2022)
Article
Optics
Tao Yu, Guangming Zhou, Yuanguang Cheng, Fuchao Hu, Tianfan Jiang, Tao Sun, Yifu Shen, Yiming Zhou, Junping Li
Summary: SLM technique with different laser volume energy density (VED) was used to prepare AlCoCrFeNi2.1 eutectic high entropy alloy. The effect of different VED on the relative density, microstructure, mechanical properties and high temperature oxidation properties of the alloy was investigated. The results showed that when the VED was raised to 187.5 J/mm3, the alloy exhibited a dual-phase (FCC and BCC) lamellar eutectic structure with a relative density of 99.51 %. The alloy had high strength and ductility, with an average microhardness of 479.04 HV, yield strength of 1151 MPa, tensile strength of 1364 MPa, and elongation at fracture of 16.37 %.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Xingyu Pan, Chunlei Qiu
Summary: Adding quasi-crystal (QC) powder particles to high entropy alloy (HEA) during selective laser melting (SLM) can enhance the strength of the alloy. The microstructure and tensile properties of the material depend on the input energy density. Optimal energy density can result in a superior microstructure with dispersive columnar gamma grains and arc-shaped B2 phase, while high energy densities can lead to an undesirable grain structure.
Article
Chemistry, Physical
Thanhung Nguyen, Ming Huang, Hongjun Li, Vannghia Tran, Sen Yang
Summary: The duplex phase Al0.25FeMnNiCrCu0.5 high entropy alloy was successfully fabricated through Laser Melting Deposition (LMD) process and its structural characteristics and tensile properties were extensively studied. The alloy exhibited a combination of high tensile strength and good ductility at room temperature.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Nanoscience & Nanotechnology
Long Xu, Yandong Jia, Shiwei Wu, Yuefei Jia, Kaikai Song, Gang Wang
Summary: The current study demonstrates the synthesis of nanoprecipitation strengthened high-entropy alloys with a hierarchical fiber-like structure and dual-phase nanoprecipitates. This combined structure exhibits exceptional high-temperature strength-plasticity synergy and has potential applications in additively manufactured alloys. It also provides a pathway for further optimization of thermostable alloy properties.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Xinsheng Chen, Jian Kong, Shuai Feng, Kewei Dong, Yuzheng Liang, Qipeng Wang, Yang Yang, Xiangkui Liu
Summary: This study achieved a superior strength-ductility combination in FCC single-phase high-entropy alloys through precipitation strengthening. By selectively laser melting and in-situ alloying, a (CoCrFeNi)94Al3Ti3 HEA was prepared, and its tensile strength significantly increased after aging treatment. The strengthening mechanism was attributed to high-density nano-scale L12-type particles, grain refinement, and remaining dislocations. The aged sample also exhibited a tensile ductility of 10.1% with the introduction of L21 and Sigma phases.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Long Xu, Yandong Jia, Zhenhui Wang, Shiwei Wu, Yuefei Jia, Chuan Geng, Jianchao Peng, Xiaohua Tan, Gang Wang
Summary: Recent studies have shown that precipitation-strengthened high-entropy alloys (HEAs) fabricated through additive manufacturing exhibit excellent mechanical performance. However, the lack of research on fatigue and fracture has restricted their engineering applications. This study focused on a dual precipitation-strengthened (FeCoNi)86Al7Ti7 HEA, prepared through selective laser melting and heat treatment, and demonstrated its improved tensile and fatigue strength. The strengthening mechanism was attributed to the resistance of L1 2 and L2 1 precipitates, which hindered crack growth and enhanced fatigue performance.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Yinuo Guo, Haijun Su, Haotian Zhou, Zhonglin Shen, Yuan Liu, Jun Zhang, Lin Liu, Hengzhi Fu
Summary: In this study, the selective laser melting (SLM) technique was used to prepare AlCoCrFeNi2.1 EHEA, achieving a good balance between strength and ductility. The SLM-ed samples exhibited a complete eutectic microstructure consisting of ultra-fine FCC and ordered B2 phases. The eutectic morphology transformed from lamellar structure to cellular structure as the laser energy input decreased. The SLM-ed AlCoCrFeNi2.1 EHEA demonstrated excellent mechanical properties, including high tensile strength, yield strength, and good ductility, which can be attributed to the ultra-fine grains and heterogeneous structure.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Yiwei Sun, Jie Liu, Jialong Wang, Kai Zhang, Li Chen, Menglong Hao
Summary: In this study, a Nb521 alloy with a relative density of 99.0% was successfully processed by SLM. The microstructure of the SLM processed Nb521 showed high dislocation density, dislocation cell structure, and a large population of low-angle grain boundaries. ZrO2 nano-dispersoids were found in the microstructure, while carbides were absent. Tensile testing revealed that the strengths of the SLM processed Nb521 were comparable or higher than those of conventionally processed counterparts, but the ductility was significantly lower due to high dislocation density, porosity, and oxide dispersoids.
Article
Chemistry, Physical
Bolun Han, Kai Feng, Zhuguo Li, Zhiyuan Wang, Yiwei Yu, Shangzhe Du
Summary: This study focuses on the influence of oxygen impurity on the additive manufacturing process of metallic materials using selective laser melting. By using an equimolar CrCoNi medium entropy alloy as an example, the research demonstrates that using oxygen-rich powder can improve strength and preserve the deformation mechanism of nano-twinning through oxide dispersion strengthening.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Materials Science, Multidisciplinary
Shuai Wang, Yang Li, Di Zhang, Yue Yang, Sunusi Marwana Manladan, Zhen Luo
Summary: AlCoCrFeNi2.1 eutectic high-entropy alloy (EHEA) produced by selective laser melting (SLM) exhibits high yield strength and ultimate tensile strength, superior to samples printed using other additive manufacturing processes.
Article
Chemistry, Physical
Yiyu Huang, Zhonghao Xie, Wenshu Li, Haoyu Chen, Bin Liu, Bingfeng Wang
Summary: In this study, dynamic impact experiments were conducted to investigate the dynamic mechanical properties of SLM-NiCrFeCoMo0.2 high entropy alloy (HEA) with different molten pool sizes. The results showed that SLM-NiCrFeCoMo0.2 HEA exhibited high impact energy absorption density and compressive strength at high strain rates. The relationship between molten pool structure and precipitation distribution was studied to understand the contribution of precipitation strengthening to the material's strength.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Xu-Han Gu, Tao Lu, Tao Zhang, Wei Guo, Ye Pan, Ting Dai
Summary: The anisotropy of microstructures and mechanical properties of FeCoNiCr0.5 high-entropy alloys prepared by selective laser melting was investigated. It was found that the alloy exhibited different microstructures and mechanical properties in different directions, leading to anisotropic behavior.
Article
Materials Science, Multidisciplinary
Jhuo-Lun Lee, Pei-Te Wang, Kai-Chi Lo, Pai-Keng Shen, Nien-Ti Tsou, Koji Kakehi, Hideyuki Murakami, Che-Wei Tsai, Stephane Gorsse, An-Chou Yeh
Summary: In this study, the tensile and creep deformation behavior of a high-entropy alloy fabricated by selective laser melting (SLM) was investigated. The issue of hot ductility drop was successfully resolved by modifying the grain boundary morphology to a serrated structure. Tensile and creep tests showed that the serrated grain boundary significantly enhanced the fracture strain and creep rupture life by a factor of 3.5 and 400, respectively. Molecular dynamic simulation further demonstrated that the serrated grain boundaries could distribute strains more evenly and provide resistance against intergranular cracking.
SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Haokai Dong, Yongjie Zhang, Goro Miyamoto, Masahiro Inomoto, Weiwen Zhang, Lehua Liu, Hao Chen, Tadashi Furuhara
Summary: This study investigates the segregation behaviors of niobium at the migrating ferrite/austenite interface with ledge structure. It is found that, for the incoherent interface, niobium atoms segregate at the less mobile terrace. The experimental measurements are well explained by theoretical calculations based on solute drag theory.
SCRIPTA MATERIALIA
(2023)
Article
Nanoscience & Nanotechnology
Tadashi Furuhara, Yongjie Zhang, Mitsutaka Sato, Goro Miyamoto, Masanori Enoki, Hiroshi Ohtani, Tokuteru Uesugi, Hiroshi Numakura
Summary: This research reveals the method of controlling nanoscale dispersion of alloy carbides/nitrides in high-strength steels and emphasizes the importance of interstitial sublattice engineering for the strengthening of alloyed steels.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Moreau Louis Etienne, Gorsse Stephane, Lambard Guillaume, Murakami Hideyuki
Summary: This study investigates the microstructure evolution and oxidation resistance of Co-Cr-Ta ternary alloys, which exhibited good oxidation resistance and formed a continuous CrTaO4 layer. Additionally, the use of a data-driven strategy for optimization of the Co-Cr-Ta composition demonstrated potential for alloy design in the future.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Kenji Hayakawa, Toshio Ogawa, Lei He, Fei Sun, Yoshitaka Adachi
Summary: We aimed to enhance the strength-ductility balance of tempered martensite steel by controlling the size distribution of cementite particles. Four types of samples with different tempering temperatures were prepared. The samples subjected to two-stage tempering had a better strength-ductility balance compared to those subjected to single-stage tempering. The inclusion of both small and large cementite particles dispersed within the matrix improved the strain concentration and coalescence of voids, leading to improved strength and elongation.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Materials Science, Multidisciplinary
Minato Kawamura, Toshio Ogawa, Fei Sun, Yoshitaka Adachi
Summary: The tensile properties of vanadium-added steels with different ferrite and pearlite hardness ratios were evaluated. The addition of vanadium resulted in finer and more equiaxed phases and increased hardness. Precipitation strengthening due to vanadium carbide and ferrite/cementite misfit causing lattice strain increment contributed to the increase in hardness.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Multidisciplinary Sciences
Sriswaroop Dasari, Abhishek Sharma, Chao Jiang, Bharat Gwalani, Wei-Chih Lin, Kai-Chi Lo, Stephane Gorsse, An-Chou Yeh, Srivilliputhur G. Srinivasan, Rajarshi Banerjee
Summary: Understanding and tailoring the local chemical ordering in random solid solutions is crucial for designing complex multicomponent alloys. A simple thermodynamic framework based on binary enthalpies of mixing is used to select optimal alloying elements to control chemical ordering in high-entropy alloys (HEAs). By combining multiple characterization techniques, it is demonstrated that controlled additions of certain elements can drive chemical ordering and significantly enhance the mechanical properties of the alloys.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Nanoscience & Nanotechnology
Advika Chesetti, Sucharita Banerjee, Sriswaroop Dasari, Mohan Sai Kiran Nartu, S. M. Varahabhatla, Abhishek Sharma, Abhishek Ramakrishnan, Daniel Satko, Stephane Gorsse, Ayman Salem, Rajarshi Banerjee
Summary: A low-density precipitation strengthened CCA, Al10Nb15Ta5Ti30Zr40, with excellent room temperature mechanical properties and high plasticity, has been successfully developed through 3D printing.
SCRIPTA MATERIALIA
(2023)
Article
Multidisciplinary Sciences
Wei Chen, Antoine Hilhorst, Georgios Bokas, Stephane Gorsse, Pascal J. Jacques, Geoffroy Hautier
Summary: Based on high-throughput density-functional theory calculations, a chemical map of single-phase equimolar high-entropy alloys is constructed, and 30,201 potential alloys are identified. The formation of these alloys is mainly driven by the complex interplay among mixing enthalpy, intermetallics formation, and melting point. Two new high-entropy alloys, AlCoMnNiV and CoFeMnNiZn, are successfully synthesized based on the predictions.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Maria Moussa, Stephane Gorsse, Jacques Huot, Jean Louis Bobet
Summary: In this study, the effects of Ti replacement by Hf and the synthesis method on microstructure and crystal structure evolution in HfxTi(1-x)NbVZr high-entropy alloy were investigated. Experimental observations and theoretical thermodynamic calculations were compared, showing good agreement for arc-melted alloys but poorer agreement for induction-melted alloys. The difference was attributed to the estimation of cooling rate and the lack of a thermodynamic database.
Editorial Material
Nanoscience & Nanotechnology
An-Chou Yeh, Stephane Gorsse, Veerle Keppens, Dustin A. Gilbert
Article
Chemistry, Physical
Tso-Wei Chen, Pei-Te Wang, Yung-Chang Kang, Bo-Cheng Wu, Nien-Ti Tsou, Uwe Glatzel, Stephane Gorsse, An-Chou Yeh
Summary: This study aims to explain the underlying mechanism of grain boundary serration and its effect on the hot workability of U720Li superalloy. It was found that different cooling rates during heat treatments resulted in different types of grain boundary serrations. The presence of Type-II boundary improved the hot formability of U720Li, allowing for a high reduction ratio without crack formation.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Physics, Applied
Sriswaroop Dasari, Abhishek Sharma, Stephane Gorsse, Advika Chesetti, Rajarshi Banerjee
Summary: The complex competition between different phase stabilities in the Al0.25CoFeNi high entropy alloy leads to non-classical phase transformation pathways and novel microstructures. At 500°C, the competition between homogeneous precipitation of L1(2) and heterogeneous precipitation of BCC/B2 phases can be studied. Isothermal annealing of the alloy at this temperature results in the formation of a transient ordered L1(2) phase followed by the eventual formation of a near equilibrium L1(2) phase. However, the true equilibrium for the alloy at 500°C is a mixture of L1(2) + B2 phases, with the B2 phase growing sluggishly from grain boundaries.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Fei Sun, Yoshihisa Mino, Toshio Ogawa, Ta-Te Chen, Yukinobu Natsume, Yoshitaka Adachi
Summary: A cellular automaton simulation model combined with Bayesian optimization was used to evaluate the austenite-ferrite phase transformation in carbon steels with different carbon concentrations during isothermal annealing at various temperatures. The simulation results showed that the incubation period for nucleation is an important factor that needs to be considered, and it is mainly affected by carbon concentration. Additionally, decreasing the initial austenite grain size can result in a decrease in the average ferrite grain size after phase transformation completion.
Article
Engineering, Manufacturing
Przemyslaw Golebiewski, Pawel Wienclaw, Jaroslaw Cimek, Pawel Socha, Dariusz Pysz, Adam Filipkowski, Grzegorz Stepniewski, Olga Czerwinska, Ireneusz Kujawa, Ryszard Stepien, Rafal Kasztelanic, Andrzej Burgs, Ryszard Buczynski
Summary: We report the development of a 3D printing process for producing soft glass optical fibers. The process involves direct printing using a miniaturized crucible and depositing straight horizontally-oriented lines to replace traditional assembly techniques. Experimental results demonstrate good performance of the printed photonic crystal fiber preform.
ADDITIVE MANUFACTURING
(2024)
