The pursuit of Ag-based alloys with both high strength and toughness has posed a longstanding chal-lenge.In this study,we investigated the cluster strengthening and grain refinement toughening mecha-nisms in fully oxi...The pursuit of Ag-based alloys with both high strength and toughness has posed a longstanding chal-lenge.In this study,we investigated the cluster strengthening and grain refinement toughening mecha-nisms in fully oxidized AgMgNi alloys,which were internally oxidized at 800℃ for 8 h under an oxy-gen atmosphere.We found that Mg-O clusters contributed to the hardening(138 HV)and strengthening(376.9 MPa)of the AgMg alloy through solid solution strengthening effects,albeit at the expense of duc-tility.To address this limitation,we introduced Ni nanoparticles into the AgMg alloy,resulting in signifi-cant grain refinement within its microstructure.Specifically,the grain size decreased from 67.2μm in the oxidized AgMg alloy to below 6.0μm in the oxidized AgMgNi alloy containing 0.3 wt%Ni.Consequently,the toughness increased significantly,rising from toughness value of 2177.9 MJ m^(-3) in the oxidized AgMg alloy to 6186.1 MJ m^(-3) in the oxidized AgMgNi alloy,representing a remarkable 2.8-fold enhancement.Furthermore,the internally oxidized AgMgNi alloy attained a strength of up to 387.6 MPa,comparable to that of the internally oxidized AgMg alloy,thereby demonstrating the successful realization of concurrent strengthening and toughening.These results collectively offer a novel approach for the design of high-performance alloys through the synergistic combination of cluster strengthening and grain refinement toughening.展开更多
Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositio...Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositions of waste superalloys. The effects of sulfuric acid temperature, concentration, leaching time, stirring speed and size of superalloys on leaching of Ni and Co from waste superalloys have been mainly investigated, and the optimum leaching conditions were determined and reported. The leaching rates for nickel and cobalt were 96.68% and 96.63%, respectively, and the contents of nickel and cobalt in leaching slag were 6.77% and 0.96%, respectively. The obtained leaching solution containing Ni and Co could be used for production of Ni and Co products after removal.展开更多
High operating temperatures generally degrade the luminous performance of color converters used in high-power,laser-driven white lighting systems.This study demonstrated that the operating temperature of LuAG:Ce films...High operating temperatures generally degrade the luminous performance of color converters used in high-power,laser-driven white lighting systems.This study demonstrated that the operating temperature of LuAG:Ce films can be significantly reduced,particularly under high-power laser excitation near the saturation threshold.This improvement was achieved by enhancing the crystallinity and increasing the Ce^(3+)content in LuAG:Ce films.LuAG:Ce films,approximately 22.17μm in thickness,were deposited on sapphire substrates via spray pyrolysis techniques.The crystallinity was controlled by the annealing temperature,while the Ce^(3+)content was regulated by the annealing atmosphere.Compared with those with a crystallinity of 75.5%,the air-annealed films with a crystallinity of 87.4%exhibited a remarkable 95.6℃decrease in operating temperature under 18 W/mm^(2)blue laser excitation.Additionally,the incorporation of a higher Ce^(3+)content through CO annealing led to a further reduction in the operating temperature.By lowering the operating temperature,LuAG:Ce films on sapphire substrates exhibit enhanced luminous performance and thermal stability under prolonged high-power laser excitation,which could inspire the design and development of advanced color converters for laser lighting applications.展开更多
LiFePO_(4)is widely used as a stable and environmentally benign cathode material.However,its reuse potential is constrained by recycling challenges and significant performance degradation after decommissioning.Therefo...LiFePO_(4)is widely used as a stable and environmentally benign cathode material.However,its reuse potential is constrained by recycling challenges and significant performance degradation after decommissioning.Therefore,how to effectively improve the electrochemical performance of regenerated LiFePO_(4)materials and enhance their stability during cycling has become the focus of current research.In this research,Sm doping was introduced to optimize regenerated LiFePO_(4)cathode materials via a plasma ball milling assisted solid-state calcination method.Comparison between spent LiFePO_(4)and Sm-doped regenerated cathodes revealed that the appropriate level of Sm doping effectively maintained the crystal structure of LiFePO_(4).It also promoted a more uniform particle morphology and a reduced particle size,which is beneficial for shortening Li^(+)transport pathways.This enhancement significantly improved electronic conductivity,leading to enhanced electrochemical performance.The 2%Sm doped regenerated material exhibited optimal performance,achieving an initial charge-discharge specific capacity of 142.2 mAh·g^(-1)at 1 C and maintaining a capacity retention of 96.5%after 200 cycles.This conclusion is of significant importance for improving resource utilization efficiency of spent LiFePO_(4)batteries.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51977027 and 51967008)the Scientific and Technological Project of Yunnan Precious Metals Lab-oratory(Nos.YPML-2023050250 and YPML-2022050206).
文摘The pursuit of Ag-based alloys with both high strength and toughness has posed a longstanding chal-lenge.In this study,we investigated the cluster strengthening and grain refinement toughening mecha-nisms in fully oxidized AgMgNi alloys,which were internally oxidized at 800℃ for 8 h under an oxy-gen atmosphere.We found that Mg-O clusters contributed to the hardening(138 HV)and strengthening(376.9 MPa)of the AgMg alloy through solid solution strengthening effects,albeit at the expense of duc-tility.To address this limitation,we introduced Ni nanoparticles into the AgMg alloy,resulting in signifi-cant grain refinement within its microstructure.Specifically,the grain size decreased from 67.2μm in the oxidized AgMg alloy to below 6.0μm in the oxidized AgMgNi alloy containing 0.3 wt%Ni.Consequently,the toughness increased significantly,rising from toughness value of 2177.9 MJ m^(-3) in the oxidized AgMg alloy to 6186.1 MJ m^(-3) in the oxidized AgMgNi alloy,representing a remarkable 2.8-fold enhancement.Furthermore,the internally oxidized AgMgNi alloy attained a strength of up to 387.6 MPa,comparable to that of the internally oxidized AgMg alloy,thereby demonstrating the successful realization of concurrent strengthening and toughening.These results collectively offer a novel approach for the design of high-performance alloys through the synergistic combination of cluster strengthening and grain refinement toughening.
文摘Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositions of waste superalloys. The effects of sulfuric acid temperature, concentration, leaching time, stirring speed and size of superalloys on leaching of Ni and Co from waste superalloys have been mainly investigated, and the optimum leaching conditions were determined and reported. The leaching rates for nickel and cobalt were 96.68% and 96.63%, respectively, and the contents of nickel and cobalt in leaching slag were 6.77% and 0.96%, respectively. The obtained leaching solution containing Ni and Co could be used for production of Ni and Co products after removal.
基金supported by the National Natural Science Foundation of China(Nos.51977027 and 51967008)the Scientific and Technological Project of Yunnan Precious Metals Laboratory(Nos.YPML-2023050250,YPML-2022050206,YPML20240502061,YPML-20240502062,and YPML-20240502091).
文摘High operating temperatures generally degrade the luminous performance of color converters used in high-power,laser-driven white lighting systems.This study demonstrated that the operating temperature of LuAG:Ce films can be significantly reduced,particularly under high-power laser excitation near the saturation threshold.This improvement was achieved by enhancing the crystallinity and increasing the Ce^(3+)content in LuAG:Ce films.LuAG:Ce films,approximately 22.17μm in thickness,were deposited on sapphire substrates via spray pyrolysis techniques.The crystallinity was controlled by the annealing temperature,while the Ce^(3+)content was regulated by the annealing atmosphere.Compared with those with a crystallinity of 75.5%,the air-annealed films with a crystallinity of 87.4%exhibited a remarkable 95.6℃decrease in operating temperature under 18 W/mm^(2)blue laser excitation.Additionally,the incorporation of a higher Ce^(3+)content through CO annealing led to a further reduction in the operating temperature.By lowering the operating temperature,LuAG:Ce films on sapphire substrates exhibit enhanced luminous performance and thermal stability under prolonged high-power laser excitation,which could inspire the design and development of advanced color converters for laser lighting applications.
基金The Yunnan Province Basic Research Program(Nos.202501AW070007 and 202201AT070184)the Yunnan Precious Metals Laboratory Technology Plan Project(YPML-20240502049)+1 种基金the High-level Talent Introduction Scientific Research Start Project of KUST(20190015)the Kunming University of Science and Technology Analysis Test Fund(2023P20221102021,2024T20180052)are gratefully acknowledged.
文摘LiFePO_(4)is widely used as a stable and environmentally benign cathode material.However,its reuse potential is constrained by recycling challenges and significant performance degradation after decommissioning.Therefore,how to effectively improve the electrochemical performance of regenerated LiFePO_(4)materials and enhance their stability during cycling has become the focus of current research.In this research,Sm doping was introduced to optimize regenerated LiFePO_(4)cathode materials via a plasma ball milling assisted solid-state calcination method.Comparison between spent LiFePO_(4)and Sm-doped regenerated cathodes revealed that the appropriate level of Sm doping effectively maintained the crystal structure of LiFePO_(4).It also promoted a more uniform particle morphology and a reduced particle size,which is beneficial for shortening Li^(+)transport pathways.This enhancement significantly improved electronic conductivity,leading to enhanced electrochemical performance.The 2%Sm doped regenerated material exhibited optimal performance,achieving an initial charge-discharge specific capacity of 142.2 mAh·g^(-1)at 1 C and maintaining a capacity retention of 96.5%after 200 cycles.This conclusion is of significant importance for improving resource utilization efficiency of spent LiFePO_(4)batteries.
