Integral thin shells made of high strength aluminum alloys are urgently needed in new generation transportation equipment. There are challenges to overcoming the co-existing problems of wrinkling and splitting by the ...Integral thin shells made of high strength aluminum alloys are urgently needed in new generation transportation equipment. There are challenges to overcoming the co-existing problems of wrinkling and splitting by the cold forming and hot forming processes. An innovative technology of ultra-low temperature forming has been invented for aluminum alloy thin shells by the new phenomenon of ‘dual enhancement effect’. That means plasticity and hardening are enhanced simultaneously at ultra-low temperatures. In this perspective, the dual enhancement effect is described, and the development, current state and prospects of this new forming method are introduced. This innovative method can provide a new approach for integral aluminum alloy components with large size, ultra-thin thickness, and high strength. An integral tank dome of rocket with 2 m in diameter was formed by using a blank sheet with the same thickness as the final component, breaking through the limit value of thickness-diameter ratio.展开更多
Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challen...Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challenges due to the dissolution of intermediate reaction products.In this work,we aim to harness the advantages of Se while reducing its limitations by preparing a core-shell mesoporous carbon hollow sphere with a titanium nitride(C@TiN)host to load 63.9wt%Se as the positive electrode material for Al-Se batteries.Using the physical and chemical confinement offered by the hollow mesoporous carbon and TiN,the obtained core-shell mesoporous carbon hollow spheres coated with Se(Se@C@TiN)display superior utilization of the active material and remarkable cycling stability.As a result,Al-Se batteries equipped with the as-prepared Se@C@TiN composite positive electrodes show an initial discharge specific capacity of 377 mAh·g^(-1)at a current density of 1000 mA·g^(-1)while maintaining a discharge specific capacity of 86.0 mAh·g^(-1)over 200 cycles.This improved cycling performance is ascribed to the high electrical conductivity of the core-shell mesoporous carbon hollow spheres and the unique three-dimensional hierarchical architecture of Se@C@TiN.展开更多
In this study, fine aluminum oxynitride (γ-AlON) powder was synthesized from a solid-state hydrolysis byproduct for the first time through in-depth research on the hydrolysis of metal Al powder. Hydrolysis begins on ...In this study, fine aluminum oxynitride (γ-AlON) powder was synthesized from a solid-state hydrolysis byproduct for the first time through in-depth research on the hydrolysis of metal Al powder. Hydrolysis begins on the surface of the Al particles, the initial solid-state hydrolysis byproduct is AlOOH and then Al(OH)_(3), and during the reaction stage, a unique core‒shell structure with a hollow outer core composite precursor is formed. Pure-phase AlON powder can be synthesized by utilizing a composite precursor with an appropriate Al_(2)O_(3)/Al ratio (Al_(2)O_(3)/Al = 10.27) under a flowing N_(2) atmosphere. The core‒shell structure decreases the diffusion distance between raw materials and reduces the nitridation temperature (1700 °C). Furthermore, the unique hollow structure of the composite precursor results in some of the synthesized AlON powder also having a hollow structure, which is conducive to powder crushing, and fine nanoscale (D50 = 292 nm) powder can be obtained only via a grinding process. The combination of Al–H_(2)O reaction and direct nitridation (DN) methods has led to the development of a new synthesis method for AlON powder and provides a new method for the recovery of the solid-state hydrolysis byproduct of metal Al powder.展开更多
The silica coated aluminum composite particles were prepared by hydrolysis–condensation polymerization of tetraethylorthosilicate(TEOS)on the surface of aluminum particle.The structure,morphology,and properties of th...The silica coated aluminum composite particles were prepared by hydrolysis–condensation polymerization of tetraethylorthosilicate(TEOS)on the surface of aluminum particle.The structure,morphology,and properties of the silica coated aluminum were studied.The peaks of Si—O—Si are presented in the Fourier transform infrared(FT-IR)spectrum of the composite particles.The thickness of the silica shell is about 80 nm according to the results of transmission electron microscopy(TEM)and laser particle size analysis,while the mean diameter of the aluminum particle is 7.13μm.The mass fraction of silica in the sample was determined by fluorescent X-ray spectrometry(XRF).Result of the thermogravimetric analysis(TGA)indicates that thermal stability of silica coated aluminum particles is better than that of pure aluminum particles at low temperature while more reactive at high temperature.展开更多
A fiber Bragg grating temperature sensor network was designed to implement the real-time health monitoring of the aluminum reduction cell. The heat transfer process was simulated using software ANSYS, and an on-line s...A fiber Bragg grating temperature sensor network was designed to implement the real-time health monitoring of the aluminum reduction cell. The heat transfer process was simulated using software ANSYS, and an on-line shell monitoring system was established based on optical sensing technology. According to aluminum reduction cell heat transfer theory, the 2D slice finite element model was developed. The relationship between shell temperature and cell status was discussed. Fiber Bragg grating （FBG） was chosen as the temperature sensor in light of its unique advantages. The accuracy of designed FBG temperature sensors exceeds 2 ~C, and good repeatability was exhibited. An interrogation system with 104 sensors based on VPG （volume phase grating） filter was established. Through the long-term monitoring on running state, the status of the aluminum reduction cell, including security and fatigue life could be acquired and estimated exactly. The obtained results provide the foundation for the production status monitoring and fault diagnosis. Long-term test results show good stability and repeatability which are compatible with electrolysis process.展开更多
基金supported by the National Key Research and Development Program of China (No.2019YFA0708800)the Fundamental Research Funds for the Central Universities (No.DUT20ZD101)。
文摘Integral thin shells made of high strength aluminum alloys are urgently needed in new generation transportation equipment. There are challenges to overcoming the co-existing problems of wrinkling and splitting by the cold forming and hot forming processes. An innovative technology of ultra-low temperature forming has been invented for aluminum alloy thin shells by the new phenomenon of ‘dual enhancement effect’. That means plasticity and hardening are enhanced simultaneously at ultra-low temperatures. In this perspective, the dual enhancement effect is described, and the development, current state and prospects of this new forming method are introduced. This innovative method can provide a new approach for integral aluminum alloy components with large size, ultra-thin thickness, and high strength. An integral tank dome of rocket with 2 m in diameter was formed by using a blank sheet with the same thickness as the final component, breaking through the limit value of thickness-diameter ratio.
基金supported by the National Natural Science Foundation of China(No.52374350)China Postdoctoral Science Foundation(Nos.2020M680347 and 2021T140051)the Fundamental Research Funds for the Central Universities(No.FRF-TP-20-045A1)。
文摘Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challenges due to the dissolution of intermediate reaction products.In this work,we aim to harness the advantages of Se while reducing its limitations by preparing a core-shell mesoporous carbon hollow sphere with a titanium nitride(C@TiN)host to load 63.9wt%Se as the positive electrode material for Al-Se batteries.Using the physical and chemical confinement offered by the hollow mesoporous carbon and TiN,the obtained core-shell mesoporous carbon hollow spheres coated with Se(Se@C@TiN)display superior utilization of the active material and remarkable cycling stability.As a result,Al-Se batteries equipped with the as-prepared Se@C@TiN composite positive electrodes show an initial discharge specific capacity of 377 mAh·g^(-1)at a current density of 1000 mA·g^(-1)while maintaining a discharge specific capacity of 86.0 mAh·g^(-1)over 200 cycles.This improved cycling performance is ascribed to the high electrical conductivity of the core-shell mesoporous carbon hollow spheres and the unique three-dimensional hierarchical architecture of Se@C@TiN.
基金financially supported by the National Key R&D Program of China(Nos.2022YFB3708500 and 2023YFB3611000)the Fujian Science&Technology Innovation Laboratory for Optoelectronic Information China(No.2020ZZ109).
文摘In this study, fine aluminum oxynitride (γ-AlON) powder was synthesized from a solid-state hydrolysis byproduct for the first time through in-depth research on the hydrolysis of metal Al powder. Hydrolysis begins on the surface of the Al particles, the initial solid-state hydrolysis byproduct is AlOOH and then Al(OH)_(3), and during the reaction stage, a unique core‒shell structure with a hollow outer core composite precursor is formed. Pure-phase AlON powder can be synthesized by utilizing a composite precursor with an appropriate Al_(2)O_(3)/Al ratio (Al_(2)O_(3)/Al = 10.27) under a flowing N_(2) atmosphere. The core‒shell structure decreases the diffusion distance between raw materials and reduces the nitridation temperature (1700 °C). Furthermore, the unique hollow structure of the composite precursor results in some of the synthesized AlON powder also having a hollow structure, which is conducive to powder crushing, and fine nanoscale (D50 = 292 nm) powder can be obtained only via a grinding process. The combination of Al–H_(2)O reaction and direct nitridation (DN) methods has led to the development of a new synthesis method for AlON powder and provides a new method for the recovery of the solid-state hydrolysis byproduct of metal Al powder.
基金Project(50306008)supported by the National Natural Science Foundation of China
文摘The silica coated aluminum composite particles were prepared by hydrolysis–condensation polymerization of tetraethylorthosilicate(TEOS)on the surface of aluminum particle.The structure,morphology,and properties of the silica coated aluminum were studied.The peaks of Si—O—Si are presented in the Fourier transform infrared(FT-IR)spectrum of the composite particles.The thickness of the silica shell is about 80 nm according to the results of transmission electron microscopy(TEM)and laser particle size analysis,while the mean diameter of the aluminum particle is 7.13μm.The mass fraction of silica in the sample was determined by fluorescent X-ray spectrometry(XRF).Result of the thermogravimetric analysis(TGA)indicates that thermal stability of silica coated aluminum particles is better than that of pure aluminum particles at low temperature while more reactive at high temperature.
基金Project(61174018) supported by National Natural Science Foundation, ChinaProject(ZR2011FQ025) supported by the Natural Science Foundation of Shandong Province ChinaProject(2010GN066) supported by the Independent Innovation Foundation of Shandong University, China
文摘A fiber Bragg grating temperature sensor network was designed to implement the real-time health monitoring of the aluminum reduction cell. The heat transfer process was simulated using software ANSYS, and an on-line shell monitoring system was established based on optical sensing technology. According to aluminum reduction cell heat transfer theory, the 2D slice finite element model was developed. The relationship between shell temperature and cell status was discussed. Fiber Bragg grating （FBG） was chosen as the temperature sensor in light of its unique advantages. The accuracy of designed FBG temperature sensors exceeds 2 ~C, and good repeatability was exhibited. An interrogation system with 104 sensors based on VPG （volume phase grating） filter was established. Through the long-term monitoring on running state, the status of the aluminum reduction cell, including security and fatigue life could be acquired and estimated exactly. The obtained results provide the foundation for the production status monitoring and fault diagnosis. Long-term test results show good stability and repeatability which are compatible with electrolysis process.
