Article
Materials Science, Multidisciplinary
Mingjun Yang, Andrey Orekhov, Zhi-Yi Hu, Man Feng, Shenbao Jin, Gang Sha, Kai Li, Vahid Samaee, Min Song, Yong Du, Gustaaf Van Tendeloo, Dominique Schryvers
Summary: In-situ TEM experiments revealed that coherent beta'' precipitates in Al alloys are sheared into small fragments by dislocations, while semi-coherent beta' precipitates are more difficult to be fragmented and can maintain their shape after tensile deformation.
Article
Nanoscience & Nanotechnology
Yang Wang, Yang Song, Yuheng Fan, Hongliang Zhao, Zhenyu Hong, Kexing Song, Xianglei Dong, Chunwen Guo
Summary: A double-peak precipitation hardening is observed in a Cu-0.75Fe-0.35Ti alloy aged at 500 degrees C, with an early hardness peak appearing after 1 h aging and a second peak after 6 h aging. Transmission electron microscopy observation shows that abundant coherent precipitates with large lattice mismatch form in the 1 h-aged specimen, leading to strong coherency strengthening and the early hardness peak. With aging time increasing to 6 h, the precipitates transform into incoherent Fe2Ti/FeTi precipitates, strengthening the alloy through the Orowan bypass mechanism and causing the second hardness peak. The 1 h-aged specimen exhibits higher hardness (181.2 HV) than the 6 h-aged one (174.8 HV), while both have comparable electrical conductivity (56.8%IACS and 59.8%IACS, respectively). Our findings suggest the possibility of designing high-performance Cu-Fe-Ti alloy with coherent precipitates through a rapid process.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Yong Heng Xu, Hong Liang Zhao, Yu Heng Fan, Zhen Yu Hong, Ke Xing Song, Xiang Lei Dong, Chun Wen Guo
Summary: The addition of Si can improve the mechanical properties and aging behavior of Cu-2.2Ni-0.4Be alloy, but it has a slight impact on the electrical conductivity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Anette B. Hagen, Sigurd Wenner, Ruben Bjorge, Di Wan, Calin D. Marioara, Randi Holmestad, Inga G. Ringdalen
Summary: Al-Mg-Si (6xxx series) alloys exhibit strong mechanical properties but are weakened by a soft precipitation free zone (PFZ) near grain boundaries during heat treatment, reducing material ductility. This study employs nanoindentation and microstructure characterization to quantitatively analyze these alloys. Experimental results confirm that the PFZ weakens the material, while an adjacent region exhibits increased hardness due to a higher density of precipitates. This previously unrecognized harder zone has important implications for the mechanical properties of large-grained aluminum alloys.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Mingjin Wu, Zhongqin Tang, Pengcheng Ye, Mengjun Long, Feifei Wu, Feng Jiang
Summary: The effect of annealing treatment on the microstructure of micro arc oxidation (MAO) ceramic film prepared on Al-Mg-Sc alloy was investigated. The results showed that the difference in the microstructure of the alloy after various annealing treatments mainly focused on the evolution of dislocation density and the precipitation of beta phase (Al3Mg2), leading to a transformation in the composition of the surface oxide film. The optimal MAO ceramic film with higher thickness and lower porosity was obtained on the alloy after annealing treatment at room temperature, providing a theoretical basis for improving the corrosion resistance of Al-Mg-Sc alloy.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
Bowen Ma, Bailing An, Xue Zhao, Yunchao Li, Jingwen Du, Engang Wang
Summary: Doping Sc can enhance the mechanical properties of Cu-Cr-Zr alloy while maintaining its electrical conductivity. The addition of Sc leads to the formation of a new intermetallic compound with Zr, which segregates at the grain boundary. The solution + rolling + aging process results in improved properties, including the formation of nanoscale precipitates and subgrains. The addition of Sc increases the ultimate tensile strength and hardness of the alloy without significant reduction in electrical conductivity, expanding its application range.
Article
Materials Science, Multidisciplinary
Jee Hyuk Ahn, Seung Zeon Han, Eun-Ae Choi, Geun Young Lee, Kwangho Kim, Jehyun Lee, Heung Nam Han
Summary: Controlling the distribution of DP and CP in Cu alloy can significantly widen the range of strength and electrical conductivity, thereby improving the performance of the alloy.
MATERIALS CHARACTERIZATION
(2022)
Article
Metallurgy & Metallurgical Engineering
Tao Li, Zhong-jun Leng, Xi-tao Wang, Shi-fang Wang, Su-qing Zhang, Yuan-sheng Yang, Ji-xue Zhou
Summary: Electroless copper plating was performed to impart electrical conductivity to the magnesium alloy micro-arc oxidation (MAO) coating. The optimized plating temperature and complexing agent concentration were found to be 60 degrees C and 30 g/L, respectively. The plated specimen achieved a square resistance of 0.03 Omega/ after the third stage, indicating excellent electrical conductivity without significantly reducing its corrosion resistance.
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
(2022)
Article
Chemistry, Physical
Yifan Wang, Yanli Lu, Shiyao Zhang, Haipeng Zhang, Hong Wang, Zheng Chen
Summary: Through TEM and tensile testing, the microstructure of nanoscale precipitates formed in the primary a-Al grains of a cast Al-7Si-Mg alloy during ageing at different temperatures has been systematically investigated. The interactions of dislocations with different types of precipitates were analyzed, revealing the strengthening effects on mechanical properties. The study also discussed the moire fringes and FFT pattern of beta phase, as well as the unique phenomenon of beta phase nucleation and growth on the surface of Si particles.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Zhenmin Lai, Kangzhen Peng, Beibei Gao, Yongjin Mai, Xiaohua Jie
Summary: An economical and practical thermo-mechanical treatment process is desired for achieving a good combination of strength and conductivity in copper alloys. In this study, a new multi-stage treatment method involving pre-rolling with small strain and short-time aging before secondary rolling and aging is implemented in Cu-Cr-Zr alloys. The results show that the strength and ductility are improved with only a slight decrease in electrical conductivity compared to conventional single-stage treatment. The pre-rolling and pre-aging processes lead to the formation of dense, dispersive, and stable shear bands with high dislocation density and fine grains. Dislocation strengthening contributes to increased yield strength, while the heterostructure comprised of microstructures inside and outside the shear bands provides good tensile plasticity. This study sheds light on the development of a simplified and cost-saving thermo-mechanical treatment process for Cu-Cr-Zr alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
P. Changizian, Z. Yao, M. R. Daymond
Summary: TEM analysis was employed to study deformation mechanisms in X-750 Ni-based superalloy, showing that planar slip resulted in the formation of planar slip bands due to low stacking fault energy and shearing of ordered gamma'-precipitates. The shearing of gamma'-precipitates occurred through APB or SF mechanisms evidenced by superlattice or stacking faults.
MATERIALS CHARACTERIZATION
(2021)
Article
Nanoscience & Nanotechnology
Yunhe Zheng, Laure Bourgeois, Jian-Feng Nie
Summary: This study investigated the structure of precipitates in Mg-Zn-Al alloys, revealing new structural features and proposing that the rod-shaped precipitates can be described by tiling of different shapes.
SCRIPTA MATERIALIA
(2021)
Article
Nanoscience & Nanotechnology
S. Y. Peng, Y. Z. Tian, Y. Yang, M. Jiang, H. X. Li, J. W. Wang, S. Li, G. W. Qin
Summary: In this study, a powder rolling strategy was successfully used to fabricate fully dense Cu-10Fe billet, solving the challenges of Fe macrosegregation during casting and limited sample size in traditional powder metallurgy methods. The microstructure evolution at different processing stages was characterized, revealing the successful avoidance of Fe macrosegregation and the achievement of good metallurgical bonding quality between powders. Moreover, the formation mechanisms of ordered structures and precipitates were analyzed, and the variation of mechanical and electrical properties with aging process was discussed.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Yuan Yu, Nannan Xu, Shengyu Zhu, Zhuhui Qiao, Jianbin Zhang, Jun Yang, Weimin Liu
Summary: The study presents a strategy to adjust the segregation form of Cu in high entropy alloy to dispersed nanoscale precipitation for improved performance. The tailored HEA material shows excellent mechanical properties, antifouling abilities, corrosion resistance, and wear resistance.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Jing-kun Li, Bin-guo Fu, Tian-shun Dong, Guo-lu Li, Yong-yue Liu, Jia-geng Liu, Chun-yang Wang, Wei Cui
Summary: A new nano-scale rhombic precipitate was discovered in SiC with 8 wt% Mg additive. TEM was used to characterize the distribution, shape, size, and microstructure of the precipitates, as well as to determine its formation mechanism. The rhombic precipitates were found to be under 65 nm in size and extensively distributed with high density. They contained a significant amount of Fe from the collision between the stainless steel pot and the milling balls, as well as Fe3Si generated during sintering. The Fe3Si precipitates and SiC matrix exhibited specific crystal orientations.
MATERIALS CHARACTERIZATION
(2023)
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)