Self-designed Al8Si0.4Mg0.4Fe aluminium alloy was modified with Sr,followed by solid solution and aging treatments to regulate its microstructure and mechanical/electrical properties.The results show that after the mo...Self-designed Al8Si0.4Mg0.4Fe aluminium alloy was modified with Sr,followed by solid solution and aging treatments to regulate its microstructure and mechanical/electrical properties.The results show that after the modification treatment,the room-temperature tensile strength of the alloy remains nearly unchanged,the elongation at break slightly increases from 1.82%to 3.34%,and the electrical conductivity significantly increases from 40.1%international annealed copper standard(IACS)to 42.0%IACS.After the modification,the alloy was subjected to solid solution treatment at 515℃for 8 h,followed by aging treatment at 180,200,220 and 240℃for 6 h.With increasing aging temperature,the electrical conductivity increases monotonously from 41.4%IACS to 45.5%IACS,while the room-temperature tensile strength initially increases and then decreases.At 200℃,the alloy achieves an optimal balance between electrical conductivity and room-temperature tensile strength:the electrical conductivity is 42.5%IACS,and the room-temperature tensile strength is 282.9 MPa.When the aging temperature continues to rise,the alloy undergoes overaging.Although the conductivity continues to increase,the room-temperature tensile strength drops sharply,and it is only 177.1 MPa at 240℃.展开更多
The current study investigates the hot deformation behavior of Al-12Ce-0.4Sc alloy with an isothermal hot compression test at300-450°C/0.001-1s^(-1).Results show that the flow curves exhibit typical dynamic recov...The current study investigates the hot deformation behavior of Al-12Ce-0.4Sc alloy with an isothermal hot compression test at300-450°C/0.001-1s^(-1).Results show that the flow curves exhibit typical dynamic recovery(DRV)and slight flow-softening behavior.Additionally,the flow curves overlap owing to the dynamic strain aging(DSA)phenomenon at 400-450°C/0.01-0.1 s^(-1).Two different constitutive models were developed using the experimental data for hot deformation:(i)strain-compensated Arrhenius model(Method I)and(ii)logistic regression model(MethodⅡ).The average stress exponent(n)and apparent activation energy(Q)are 14.25 and 209.58 k J·mol^(-1),respectively.The hot-working processing map shows that the optimal processing condition is 400°C/1 s^(-1),and the maximum power dissipation efficiency is 22%.Stable and unstable domains indicated by the processing map were correlated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),and electron backscatter diffraction(EBSD)characterization techniques.The unstable domains are primarily associated with pro-eutectic Al11Ce3intermetallic fracture and interfacial cracks betweenα-Al and pro-eutectic Al_(11)Ce_(3).展开更多
Electrocatalytic toluene(TL)oxidation to produce benzoic acid(BAC)process is largely hindered due to sluggish kinetics associated with the transformation of the rate-determining step,because of weak TL adsorption and ...Electrocatalytic toluene(TL)oxidation to produce benzoic acid(BAC)process is largely hindered due to sluggish kinetics associated with the transformation of the rate-determining step,because of weak TL adsorption and high rate-determining step energy barrier for difficult to dehydrogenate.Herein,we report Mn_(x)Ce_(1-x)O_(2)/CNT catalyst for accelerated reaction kinetics.Theoretical and experimental studies indicate that Ce sites promote TL adsorption and polyvalent Mn modulates the electronic structure of Ce sites reducing the rate-determining step energy barrier.This results in increasing^(*)C_(6)H_(5)CH_(2)coverage and effectively accelerating TL oxidation reaction(TOR)kinetics.Excitingly,the Faraday efficiency(FE)and BAC yield of optimized Mn_(0.6)Ce_(0.4)O_(2)/CNT at 2.6 V vs.RHE could reach 85.9%and 653.9 mg h^(-1)cm^(-2),respectively.In addition,the Mn_(0.6)Ce_(0.4)O_(2)/CNT displays a high selectivity of 96.3%for BAC.Combining the TL oxidation reaction with hydrogen evolution reaction,the anion exchange membrane electrolyzer of Mn_(0.6)Ce_(0.4)O_(2)/CNT(+)||Pt/C(-)can reach 100 mA cm^(-2)at the voltage of 3.0 V,in which the BAC yield is 579.4 mg h^(-1)cm^(-2)and the FE is 83.6%.This work achieved high selectivity of TOR at industrial-relevant current densities of 100 mA cm^(-2)at the low voltage for the first time.展开更多
基金Applied Basic Research Program of Liaoning Province(CN)(2022JH2/101300078)。
文摘Self-designed Al8Si0.4Mg0.4Fe aluminium alloy was modified with Sr,followed by solid solution and aging treatments to regulate its microstructure and mechanical/electrical properties.The results show that after the modification treatment,the room-temperature tensile strength of the alloy remains nearly unchanged,the elongation at break slightly increases from 1.82%to 3.34%,and the electrical conductivity significantly increases from 40.1%international annealed copper standard(IACS)to 42.0%IACS.After the modification,the alloy was subjected to solid solution treatment at 515℃for 8 h,followed by aging treatment at 180,200,220 and 240℃for 6 h.With increasing aging temperature,the electrical conductivity increases monotonously from 41.4%IACS to 45.5%IACS,while the room-temperature tensile strength initially increases and then decreases.At 200℃,the alloy achieves an optimal balance between electrical conductivity and room-temperature tensile strength:the electrical conductivity is 42.5%IACS,and the room-temperature tensile strength is 282.9 MPa.When the aging temperature continues to rise,the alloy undergoes overaging.Although the conductivity continues to increase,the room-temperature tensile strength drops sharply,and it is only 177.1 MPa at 240℃.
基金financially supported by the Science and Engineering Research Board(SERB),Government of India(No.EEQ/2020/000306)。
文摘The current study investigates the hot deformation behavior of Al-12Ce-0.4Sc alloy with an isothermal hot compression test at300-450°C/0.001-1s^(-1).Results show that the flow curves exhibit typical dynamic recovery(DRV)and slight flow-softening behavior.Additionally,the flow curves overlap owing to the dynamic strain aging(DSA)phenomenon at 400-450°C/0.01-0.1 s^(-1).Two different constitutive models were developed using the experimental data for hot deformation:(i)strain-compensated Arrhenius model(Method I)and(ii)logistic regression model(MethodⅡ).The average stress exponent(n)and apparent activation energy(Q)are 14.25 and 209.58 k J·mol^(-1),respectively.The hot-working processing map shows that the optimal processing condition is 400°C/1 s^(-1),and the maximum power dissipation efficiency is 22%.Stable and unstable domains indicated by the processing map were correlated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),and electron backscatter diffraction(EBSD)characterization techniques.The unstable domains are primarily associated with pro-eutectic Al11Ce3intermetallic fracture and interfacial cracks betweenα-Al and pro-eutectic Al_(11)Ce_(3).
基金supported by the National Natural Science Foundation of China(52272222)the Taishan Scholar Young Talent Program(tsqn201909114,tsqn201909123)the University Youth Innovation Team of Shandong Province(202201010318)。
文摘Electrocatalytic toluene(TL)oxidation to produce benzoic acid(BAC)process is largely hindered due to sluggish kinetics associated with the transformation of the rate-determining step,because of weak TL adsorption and high rate-determining step energy barrier for difficult to dehydrogenate.Herein,we report Mn_(x)Ce_(1-x)O_(2)/CNT catalyst for accelerated reaction kinetics.Theoretical and experimental studies indicate that Ce sites promote TL adsorption and polyvalent Mn modulates the electronic structure of Ce sites reducing the rate-determining step energy barrier.This results in increasing^(*)C_(6)H_(5)CH_(2)coverage and effectively accelerating TL oxidation reaction(TOR)kinetics.Excitingly,the Faraday efficiency(FE)and BAC yield of optimized Mn_(0.6)Ce_(0.4)O_(2)/CNT at 2.6 V vs.RHE could reach 85.9%and 653.9 mg h^(-1)cm^(-2),respectively.In addition,the Mn_(0.6)Ce_(0.4)O_(2)/CNT displays a high selectivity of 96.3%for BAC.Combining the TL oxidation reaction with hydrogen evolution reaction,the anion exchange membrane electrolyzer of Mn_(0.6)Ce_(0.4)O_(2)/CNT(+)||Pt/C(-)can reach 100 mA cm^(-2)at the voltage of 3.0 V,in which the BAC yield is 579.4 mg h^(-1)cm^(-2)and the FE is 83.6%.This work achieved high selectivity of TOR at industrial-relevant current densities of 100 mA cm^(-2)at the low voltage for the first time.
