Article
Materials Science, Multidisciplinary
Tao Wei, Yadong Wang, Zhenghua Tang, Sufen Xiao
Summary: The true stress-strain curve of Al-Mg-Si-Cu-Zn alloy under high temperature and high strain rate conditions was obtained, and the constitutive equation was established. The optimum hot working window was determined based on the comparison of predicted values from the model with experimental values.
MATERIALS TODAY COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Chang-Hee Cho, Dal-Oh Kim, Kwangtae Son, Hyun-Soon Park
Summary: Al-Zn-Mg-Cu alloys exhibit the best mechanical properties among aluminum alloys, but suffer from poor formability during metalworking processes. This study investigates the high-temperature deformation behavior and mechanisms of an Al-Zn-Mg-Cu alloy, highlighting flow instabilities at higher strain rates and cooler temperatures, reduced recrystallization, diminished power dissipation efficiencies, and notable alpha-fiber generation.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Jun Cai, Lin Chen, Juan Yang, Wen Wang, Ben Ding, Qingxiang Yang, Ke Qiao, Kuaishe Wang
Summary: In this study, an isothermal compression experiment was conducted to investigate the rheological behavior of Al-4.57Zn-1.50Mg-1.92Cu high-strength aluminum alloy. The strain rate and temperature were found to significantly affect the flow stress level. A constitutive equation was established and proven to accurately predict the performance. Additionally, a processing map was created to assess deformation safety, and the microstructure evolution was observed using various microscopy techniques. The findings indicated that dynamic recovery and small-scale dynamic recrystallization played a major role in the softening mechanism during hot deformation, and dynamic recrystallization had a significant impact on the alloy's hot deformation behavior.
Article
Materials Science, Multidisciplinary
Ding-ge Fan, Kun-kun Deng, Cui-ju Wang, Kai-bo Nie, Quan-xin Shi, Wei Liang
Summary: The addition of trace SiCp reduces the activation energy of the Mg-5Zn alloy, and the optimal deformation conditions were determined based on the processing map. The study also looked at the influence of PDZ size on the activation energy, as well as the effect of SiCp on the dynamic recrystallization behavior.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Materials Science, Multidisciplinary
Hua Wang, Dengfeng Yin, Ming-Chun Zhao, Yan Tian, Andrej Atrens
Summary: Hot deformation behavior and associated microstructural evolution in a quaternary Al-Cu-Li-Zn alloy were studied under different deformation conditions. The study found that dynamic recrystallization (DRX) was influenced by grain orientation and particle simulated nucleation (PSN) was the primary mechanism of DRX. Additionally, only a small fraction of DRX grains appeared under certain temperature and strain rate conditions.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Minbao Wu, Wu Wei, Rui Zuo, Shengping Wen, Wei Shi, Xiaorong Zhou, Xiaolan Wu, Kunyuan Gao, Hui Huang, Zuoren Nie
Summary: The hot compression behavior of a homogenized Al-5.2Mg-0.6Mn-0.29Zn-0.16Er-0.12Zr alloy was investigated under different deformation conditions. The relationship between stress, strain rate, and deformation temperature was analyzed, and a constitutive equation was established. The addition of Er and Zr into the alloy resulted in grain refinement, precipitation strengthening, and the formation of Al-3(Er, Zr) phase. Dynamic recovery was dominant during hot deformation, while dynamic recrystallization was inhibited. The alloy showed a high activation energy for hot deformation, attributed to the pinning effect of Er and Zr precipitates. The processing map helped determine the suitable process parameters for hot deformation.
Article
Materials Science, Multidisciplinary
Daoguang He, Han Xie, Y. C. Lin, Xin-Tao Yan, Zhengbing Xu, Gang Xiao
Summary: The high-temperature flow features of the Al Zn Mg Cu Zr aluminum alloy were investigated through hot compression tests. The evolution mechanisms of dislocation clusters, subgrain, and dynamic recrystallization (DRX) grains were thoroughly explored. It was found that high strain rate promotes the formation of dislocation clusters and subgrain nucleation/accumulation, leading to an increase in flow stress; however, at higher temperatures, the noticeable annihilation of substructures and the growth of DRX grains result in a decrease in flow stress. Three types of DRX nucleating mechanisms are activated during hot compression. The physically based (PB) model accurately predicts the true stresses and microstructure evolution features of the alloy.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Nanoscience & Nanotechnology
T. Nakata, Z. H. Li, T. T. Sasaki, K. Hono, S. Kamado
Summary: This study reports the influence of grain boundary segregation on microstructure development during hot-rolling of AZ31 alloy. Annealing at 420 degrees C induces strong grain boundary segregation, promoting dynamic recrystallization and strong basal texture. Annealing at 500 degrees C reduces grain boundary segregation, hindering dynamic recrystallization and resulting in a weak rolling-direction-split texture, improving the stretch formability of the alloy sheet.
SCRIPTA MATERIALIA
(2022)
Article
Chemistry, Physical
Xiong Zhou, Qichi Le, Chenglu Hu, Dandan Li, Tong Wang, Qiyu Liao, Ruizhen Guo, Chunming Liu, Xiaotao Liu
Summary: The hot deformation behavior of homogenized Mg-1.4Sn-0.93Zn-0.83Ca-0.67Mn-0.39Al alloy was studied, and a constitutive equation and hot processing map were successfully established. The results showed that the hot processing of this alloy should avoid the low-temperature area, and the optimum stable deformation areas were identified. Detailed microstructural studies revealed the crucial role of dynamic recrystallization in the alloy's stability, and the mechanisms involved were identified. In addition, the analysis of in-grain misorientation axes demonstrated the activation of non-basal slips during deformation.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
G. Y. Zheng, X. Luo, Z. D. Kou, B. Huang, Y. Q. Yang
Summary: This paper systematically investigates the microstructural evolution of Al-Zn-Mg-Cu alloy during ultrasonic surface rolling process. The results show that the microstructural evolution at different depths of the surface deformation layer is basically the same but faster closer to the surface. The basic microstructural evolution order of the alloy includes scattered dislocation, dislocation cells, elongated dense dislocation cell walls, thick laminated structure, and nanolaminated structure. The study provides a theoretical basis for adjusting the actual processing technology.
MATERIALS CHARACTERIZATION
(2022)
Article
Materials Science, Multidisciplinary
Hao Xindi, Ren Dong, Dong Juan, Haiming Zong, Lv Zhengfeng
Summary: Isothermal compression tests were conducted on 7A21 aluminum alloy using a Gleeble-3500 thermal simulator, and constitutive models with/without strain compensation based on Arrhenius type were established. Hot processing maps were constructed using a dynamic material model, and a safety strain rates map was developed to simplify the acquisition of safety zones throughout the deformation process. The model with strain compensation showed higher prediction accuracy compared to the model without strain compensation.
MATERIALS RESEARCH EXPRESS
(2021)
Article
Chemistry, Physical
Jiangtao Guo, Shengli Guo, Yazhao Shen, Defu Li
Summary: The deformation behavior of the as-extruded Mg-Li-Al-Zn-Si alloy was studied and it was found that the optimum hot deformation region was at a temperature range of 270-300 degrees C and a strain rate of 0.7. The unsafe domains showed uneven flow behavior and microstructure. The observation revealed that dynamic recrystallization easily occurred in the safe domain with high power dissipation efficiency.
Article
Chemistry, Physical
Enze Diao, Jianzhong Fan, Zhiyu Yang, Zhaochong Lv, Hao Gao, Junhui Nie
Summary: A systematic and comprehensive analysis of the hot deformation and mechanisms of SiC particle-reinforced aluminum matrix composites is significant for optimizing the processing of the composites and obtaining the desired components. Through hot compression experiments and metallographic analysis, it was found that the dominant deformation mechanism and fracture failure mode of the composite material changed under certain process conditions.
Article
Chemistry, Physical
Xiaomin Huang, Ben Guan, Baoyu Wang, Yong Zang
Summary: Isothermal tensile tests are conducted on 2195-O Al-Li alloy to investigate its hot deformation behavior. The results show that the established constitutive equation accurately predicts the deformation behavior of the alloy. The fracture mechanism of the tensile specimens changes from ductile fracture to brittle fracture as the temperature increases. The average grain size of the specimens increases with increasing temperature, but coarsening occurs at higher temperatures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Guo -lei Liu, Zhi-yong You, Wei -li Cheng, Lin Luo, Hui Yu, Li -fei Wang, Hang Li, Ze-qin Cui, Jin -hui Wang
Summary: This study investigates the dynamic recrystallization mechanism and hot deformation behavior of the Mg-0.5Bi-0.5Sn-0.5Mn alloy. The results show a strong correlation and suggest that cross-slip is the primary deformation mechanism. The processing maps indicate the most suitable processing conditions, and the occurrence of continuous and discontinuous dynamic recrystallization under different deformation conditions is observed.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Nanoscience & Nanotechnology
Juangang Zhao, Zhiyi Liu, Song Bai, Tiantian Huang, Jian Wang, Haoyu Xie, Diping Zeng, Lei Luo
Summary: In this study, a new four-stage aging treatment was designed to improve the thermal stability of the Al-Zn-Mg-Cu alloy for oil drilling applications. The natural aging process was found to accelerate Mg atom diffusion and promote the precipitation of GP zones during re-aging. Furthermore, the coarsening of precipitates with increasing thermal exposure time was observed in all aging samples.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Jian Wang, Zhiyi Liu, Song Bai, Jing Cao, Juangang Zhao, Lei Luo, Junlin Li
Summary: The microstructures, hardness distribution and strengthening mechanisms of the electron-beam welded joints of cast Al-Cu-Mg-Ag alloy plate were investigated. It was found that the precipitation of fine Omega, theta' plates and dispersed precipitates after post-welding heat treatment is the main reason for the increase in strength of the welded joint.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Bing-Bing Peng, Xiang-Ming Li, Xian Wang, Jian Mo, Lei Luo
Summary: In this study, the solidification structure of a Ti-6Al-4V ingot was numerically simulated using the CAFE method, with results showing good agreement with experimental data. It was found that reducing the pouring temperature led to grain refinement and decreased volatilization of Al, while increasing the pulling speed initially increased and then decreased the number of grains, with a corresponding trend of decreasing and then increasing average grain size. Additionally, the maximum grain size consistently increased with higher pulling speeds, indicating that a fine solidified structure with fine grains can be achieved at specific process parameters.
MATERIALS RESEARCH EXPRESS
(2021)
Article
Materials Science, Multidisciplinary
Jian Mo, Xiang-Ming Li, Lei Luo, Bing-Bing Peng
Summary: The phase field model is established and solved using the finite difference method to investigate the tilted eutectic interface morphology under isothermal and directional solidification conditions. The simulation results reveal the effects of various factors on the evolution of the tilted eutectic structure, providing insights into the growth mechanism of the structure. Instability phenomena such as bifurcation or merger and fault lines are also observed during eutectic growth.
MATERIALS RESEARCH EXPRESS
(2021)
Article
Materials Science, Multidisciplinary
Lei Luo, Zhiyi Liu, Song Bai, Jing Cao, Fei Liu, Linnan Ou, Juangang Zhao
Summary: This study investigates the microstructures and mechanical properties of a hot extruded Al-Zn-Mg-Cu alloy pipe with variable cross-section. It is found that the changes in hot deformation degrees contribute to the variable temperature distribution along the extrusion direction. The profiles of the extruded pipe exhibit dynamic recovery (DRV), partial dynamic recrystallization (DRX), and an exponential increase in high-angle grain boundaries fraction.
METALS AND MATERIALS INTERNATIONAL
(2022)
Article
Engineering, Mechanical
Chen Zhang, Lei Luo, Bingwei Chen, Wei Chen
Summary: The study investigated the effect of different coatings on the wear of the piston-cylinder system. The results showed that the graphite coating had the least improvement, the MAO coating caused serious wear in the face contact friction pair, while the HA coating exhibited good wear resistance in both line contact and face contact friction pairs.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2022)
Article
Energy & Fuels
Chen Zhang, Lei Luo, Wei Chen, Fei Yang, Gang Luo, Junming Xu
Summary: Experimental results show that using bio-jet fuel as a substitute for RP-3 jet fuel is feasible, although knock combustion is more likely to occur at large throttle openings, requiring cooling air to reduce the heat generated from spontaneous combustion.
Article
Computer Science, Artificial Intelligence
Hangcheng Dong, Jingxiao Liao, Yang Wang, Yixin Chen, Bingguo Liu, Dong Ye, Guodong Liu
Summary: In this work, the authors study the 1-D optimal piecewise linear approximation problem and propose a lattice neural network (LNN) method to solve it. They characterize the optimal solution and demonstrate the competitiveness of the LNN method through experiments.
Article
Chemistry, Analytical
Xiaobei Liang, Jinyong Yao, Lei Luo, Wenzhao Zhu, Weifang Zhang, Yanrong Wang
Summary: This paper proposes a new proportional FxRLS (PFxRLS) algorithm to solve the sensitivity and tracking performance limitations of the traditional FxRLS algorithm. The algorithm successfully reduces the sensitivity to user-defined parameters and improves robustness and denoising performance through the introduction of momentum technique.
Article
Chemistry, Physical
Lei Luo, Zhongde Shan, Haoqin Yang, Yanqing Su, Liangshun Luo, Liang Wang, Jingjie Guo, Hengzhi Fu
Summary: This study uses a combination of travelling magnetic fields and sequential solidification to optimize the Ni-rich intermetallic in Al-Cu-based alloys with high Ni content, improving their performance at both room and elevated temperatures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Lei Luo, Hao Lu, Xuemei Liu, Haibin Wang, Chao Liu, Mingsheng Wang, Xiaoyan Song
Summary: This study quantified the deformation characteristics of ceramic phase and metal binder in WC-Co cermets and proposed the mechanisms for plastic deformation. It revealed the dominant deformation mechanism and the contributions of different components to the plasticity of the cermets.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Wei Li, Huijun Liang, Dongbin Xia, Jie Fu, Lei Luo, Miao Yu
Summary: In this paper, a fuzzy PI control strategy for the magnetorheological damper (MRD) current driver is proposed, which can adapt to parameter changes and ensure accurate current output.
Article
Engineering, Multidisciplinary
Jing-Xiao Liao, Hang-Cheng Dong, Lei Luo, Jinwei Sun, Shiping Zhang
Summary: We propose a novel multi-objective criterion that combines kurtosis and G-l1/l2 norm to improve the global optimality of blind deconvolution methods. By introducing a multi-task 1DCNN with two branches, we optimize the criterion in both time and frequency domains simultaneously. Experimental results show that our method outperforms other state-of-the-art blind deconvolution methods.
MEASUREMENT SCIENCE AND TECHNOLOGY
(2023)
Article
Biology
Xiao-Cong Zhong, Qisong Wang, Dan Liu, Jing-Xiao Liao, Runze Yang, Sanhe Duan, Guohua Ding, Jinwei Sun
Summary: In this paper, a deep domain adaptation framework with correlation alignment (DDAF-CORAL) is proposed to address the problem of distribution divergence in motor imagery classification across domains.
COMPUTERS IN BIOLOGY AND MEDICINE
(2023)
Article
Engineering, Electrical & Electronic
Jing-Xiao Liao, Hang-Cheng Dong, Zhi-Qi Sun, Jinwei Sun, Shiping Zhang, Feng-Lei Fan
Summary: Bearing fault diagnosis is crucial for reducing damage risk and improving economic profits of rotating machines. Machine learning, particularly deep learning, has advanced in this field, but faces challenges in effectiveness and interpretability. To address this, a convolutional network with quadratic neurons is proposed to handle noisy bearing data, and an attention mechanism called "qttention" is derived to improve interpretability. Experiments show that the proposed network facilitates effective and interpretable bearing fault diagnosis. The code is available at https://github.com/asdvfghg/QCNN_for_bearing_diagnosis.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
