Article
Materials Science, Multidisciplinary
Priyanka Agrawal, S. Karthikeyan, Surendra Kumar Makineni, Baptiste Gault, Dipankar Banerjee
Summary: A dynamic strain aging (DSA) regime is established in a near-a titanium alloy through constant strain rate tests, with jogged screw dislocations dominating the dislocation structure within slip bands. The model predicts a DSA peak at 673-723K, with C and Si as solute species responsible for DSA, but dominated by C in this temperature and strain rate regime. Atom probe tomography confirms C and Si segregation at the dislocations, supporting the model.
Article
Engineering, Mechanical
K. U. Yazar, S. Bahl, S. Mishra, V. K. Sahu, A. Bhattacharjee, D. Banerjee, S. Suwas
Summary: This study investigates the normal and dwell fatigue response of a near alpha titanium alloy. Microcracks formed at very early stages of dwell fatigue were found to be the major reason for the decreased fatigue life. The initiation of these cracks was strongly influenced by the local crystallography of the constituent grains. A modified pile up model was used to explain the micromechanisms of crack nucleation in dwell fatigue.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Metallurgy & Metallurgical Engineering
Litton Bhandari, Jalaj Kumar, I. Balasundar, Amit Arora
Summary: The effect of heat treatment on the microstructure and high-cycle fatigue behavior of near-alpha titanium alloy IMI 834 used in aero-engine components has been studied. Significant impact of quench media on high-cycle fatigue life was observed. A fatigue model for the alloy was developed through fractographic investigations and a generalized stress-life model derived from fatigue data.
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2021)
Article
Engineering, Mechanical
R. Kumar, S. Sanyal, J. Bhagyaraj, E. Hari Krishna, S. Mukherjee, K. Prasad, S. Mandal
Summary: This study investigates the thermomechanical fatigue (TMF) behavior of Timetal 834 alloy under different loading conditions. The results show that the alloy exhibits different cyclic hardening and softening responses at different strain amplitudes. The strain amplitude and phase angle have significant effects on the TMF life.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Nanoscience & Nanotechnology
T. Mahender, M. R. Anantha Padmanaban, I. Balasundar, T. Raghu
Summary: The microstructural features of titanium alloys are influenced by post deformation heat treatment parameters, which in turn affect the mechanical properties. This study evaluated the effects of solution treatment temperature and cooling rate on the microstructure and room temperature tensile properties of an α/β titanium alloy, and attempted to establish the correlation between heat treatment parameters and resulting tensile properties using response surface methodology.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Mechanical
Jiawei Wang, Tao Guo, Yanmeng Chen, Xiaobo Wang, Pu Geng, Kewei Gao, Xiaolu Pang
Summary: The purpose of this paper is to examine the impact of TiN coating and TiN/AlN superlattice coating on the fatigue performance of titanium alloys. The study focuses on the interaction between the coating and the substrate to understand the influence of the coating on the fatigue properties of titanium alloys. The results demonstrate that the TiN/AlN superlattice coating, which possesses high hardness and fracture toughness, effectively suppresses strain localization on the surface, alters the initiation site of fatigue cracks, and enhances the fatigue strength by 23.7% at 10^7 cycles. Dislocation redistribution and secondary slip in the titanium alloys were observed as mechanisms to eliminate stress concentration.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Nanoscience & Nanotechnology
Shuxin Shen, Bei He, Huaming Wang
Summary: This study investigates the cyclic deformation behavior and softening mechanism of LDEDed and beta-forging TC17 titanium alloys. The experimental results show that cyclic softening occurs with smaller stress amplitude and larger plastic strain in LDEDed specimens compared to the wrought specimens. The size of alpha p decreases with increased strain in LDEDed specimens, while the size and shape of alpha p and alpha s in wrought specimens remain relatively unchanged. The dominant dislocation forms for cyclic softening are slip bands in the alpha phase and dislocation tangles in the beta matrix.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Nanoscience & Nanotechnology
Shuxin Shen, Bei He, Huaming Wang
Summary: This study used laser direct energy deposition technology to produce hybrid manufactured TC17 titanium alloy. The cyclic deformation behavior and dislocation morphology were investigated at different total strain ranges. The results showed that all the specimens exhibited cyclic softening when the total strain range exceeded 1.5%. Fracture occurred in the deposition zone of the hybrid manufactured specimens, and the size of the deformed alpha phase decreased with increased strain. Slip transfer and a small amount of dislocation tanglement were observed in the specimen with a strain of 1.5%, indicating cyclic hardening. The dislocation density in the beta phase increased abruptly at a strain range of 2.5%, promoting cyclic softening. Heterogeneous deformation between high and low density dislocation zones in the alpha phase of the cyclic softening samples caused deformation and fracture. The tension-compression asymmetry under forward and reverse loading revealed the presence of the Bauschinger effect. Dislocation tanglement increased local back stress, promoting cyclic softening. At the same time, back stress facilitated easier dislocation movement during reverse loading. Dislocation rearrangement and annihilation reduced friction stress and further accelerated cyclic softening.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Jin Ma, Qiang Wang, Tingyan Zhang, Hui Cao, Yongbiao Yang, Zhimin Zhang
Summary: In this study, the anisotropic behavior and fatigue performance of 7075 Al alloy in different directions were investigated. The results showed significant differences in mechanical properties among different directions and the YS and UTS increased with aging time. The fatigue life also varied in different directions and under different strain amplitudes.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Engineering, Mechanical
Thomas Edward James Edwards, Fabio Di Gioacchino, William John Clegg
Summary: In a lamellar TiAl alloy, plastic deformation mainly occurs in soft-mode colonies through slip parallel to the lamellae and near lamellar interfaces under high cycle tensile fatigue conditions. At 25 degrees C, the maximum applied stress has a greater influence on the number of slip bands than the number of loading cycles.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
Litton Bhandari, Vidit Gaur
Summary: This study investigates the cyclic behavior and cold dwell sensitivity of additively manufactured Ti6Al4V alloy. Low cycle fatigue tests were conducted on specimens exposed to a dwell period, revealing a significant reduction in fatigue lives at lower strain amplitudes but similar lives at higher ones. Fractographic analysis identified multiple crack initiation regions, attributed to process-induced defects or facet formation in α laths. The study discusses the failure mechanism based on stress redistribution and relaxation.
ENGINEERING FAILURE ANALYSIS
(2023)
Article
Engineering, Mechanical
Chengyan Bai, Liang Lan, Ruyi Xin, Shuang Gao, Bo He
Summary: The low cycle fatigue behavior of Ti-6Al-4 V alloy manufactured via electron beam melting (EBM) was studied. The relationship between fatigue property, internal stress and microstructure was established to understand the cyclic-deformation behavior and LCF life of EBM Ti-6Al-4 V alloy. It was found that the LCF life of EBM Ti-6Al-4 V is comparable to the wrought counterparts under low strains and higher than that of selective laser melted Ti-6Al-4 V reported. Tension-compression asymmetry and cyclic softening behavior were observed at different strains, and the anisotropy of tension-compression increased with increasing strain due to the increase of back stress and the decrease of friction stress. The formation of sub-grain boundaries and fragmented beta phase reduced friction stress, resulting in cyclic softening.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Materials Science, Multidisciplinary
Junfeng Luo, Guojin Xu, Qiaoxia Zhang, Yongjun Li, Jinjiang He
Summary: In this paper, the high-cycle fatigue mechanisms of a pseudoelastic NiTi shape memory alloy under different mean strains were investigated. The results show that the mean strain has an effect on the high-cycle fatigue life of NiTi, which is attributed to the inhomogeneous transformation of martensite and the phenomenon of grain reorientation/rotation.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Engineering, Mechanical
Shouwen Shi, Haiyan Li, Jianpeng Cui, Xu Chen
Summary: The multiaxial low cycle fatigue behavior of nickel-based alloy 690 at 350 degrees C was studied. The presence of short-range order (SRO) and dynamic strain aging (DSA) contributes to the formation of multi-slip planar dislocation configuration under non-proportional loading paths. The effect of multiaxial loading paths on DSA was quantitatively evaluated based on average stress drop, with axial strain amplitude dominating and cross-slip strength weakening the effect.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Nanoscience & Nanotechnology
Qinan Han, Xusheng Lei, Hao Yang, Xiaolin Yang, Zimu Su, Shao-Shi Rui, Nan Wang, Xianfeng Ma, Haitao Cui, Huiji Shi
Summary: This paper investigates the effects of temperature and load on the distribution of geometrically necessary dislocation (GND) induced by fretting fatigue in titanium alloy. The results show that both temperature and load have significant effects on GND densities, with an increase in temperature and load leading to a rise in GND densities. The peak positions of GND density correspond well with crack formation locations, indicating a close relationship between GND concentration and fretting fatigue crack formation.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
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)