This study was conducted to discuss the effect of rolling strain on microstructure and tensile properties of dual-phase Mg-8Li-3Al-2Zn-0.5 Y（wt%） alloy, which was prepared by casting, and then homogenized and rolled...This study was conducted to discuss the effect of rolling strain on microstructure and tensile properties of dual-phase Mg-8Li-3Al-2Zn-0.5 Y（wt%） alloy, which was prepared by casting, and then homogenized and rolled at 200℃. The rolling process was conducted with 10% reduction per pass and five different accumulated strains, varying from 10% to 70%. The results indicate that the as-cast and as-rolled Mg-8Li-3Al-2Zn-0.5Y alloys are composed of α-Mg, β-Li, AlLi and Al;Y phases. After rolling process,anisotropic microstructure was observed. a-Mg phase got elongated in both rolling direction and transverse direction with the addition of rolling strain. Consequently, the strength of the alloy in both directions was notably improved whereas the elongation declined, mainly caused by strain hardening and dispersion strengthening. The tensile properties of the as-rolled alloys in the RD, no matter the YS, UTS or the elongation, are higher than those of the TD due to their larger deformation strain and significant anisotropy in the hcp α-Mg phase. In addition, the fracture and strengthening mechanism of the tested alloys were also investigated systematically.展开更多
The application of all-solid-state Li-metal batteries with solid oxide electrolytes is hindered by interfacial issues,especially the solid electrolyte/Li-metal interface.This work introduced a uniform indium film laye...The application of all-solid-state Li-metal batteries with solid oxide electrolytes is hindered by interfacial issues,especially the solid electrolyte/Li-metal interface.This work introduced a uniform indium film layer on the surface of Na^(+)super ionic conductor(NASICON)solid electrolyte Li_(1.5)Al_(0.5)Ge_(1.5)P_(3)O_(12)(LAGP),which promotes the intimate contact between Li metal and solid electrolyte and hinders the side reactions at the interface.Electrochemical impedance spectra show that the battery with coated solid electrolyte presents a smaller interfacial resistance and maintains stability after a long cycling time.By contrast,the baseline battery with a pure LAGP pellet shows a contact loss after cycling with the vibration of interfacial impedance.The Li symmetric cells with indium-modified solid electrolyte present stable cycling behavior over 400 h at 0.1 and 0.2 mA·cm^(−2).The all-solid-state Li-metal batteries with a Li anode,indium coating LAGP and two kinds of cathodes,namely carbon nanotubes(CNTs)and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811),are prepared and tested.The CNTs cathode for Li-O2 and Li-air batteries has a higher specific capacity than traditional Li-ion battery cathodes.The Li-NCM811 batteries deliver an initial Coulombic efficiency of about 75%,with 82%capacity retention after 20 cycles.展开更多
The Li 4.4Al 0.4Si 0.6O 4-xLi 3BO 3 (x=0 to 0.5) ion conductors were prepared by the sol-gel method. The powder and sintered samples were characterized by DTA-TG, XRD, SEM and ac impedance techniqu...The Li 4.4Al 0.4Si 0.6O 4-xLi 3BO 3 (x=0 to 0.5) ion conductors were prepared by the sol-gel method. The powder and sintered samples were characterized by DTA-TG, XRD, SEM and ac impedance techniques. The temperature of the preparation of powder patterns decreased by this method as compared to that of the preparation in solid state reaction. The conductivity and sinterability increased with Li 3BO 3 increasing from x=0 to 0.2 in the Li 4.4Al 0.4Si 0.6O 4-xLi 3BO 3 solid electrolytes. The particle size of the sintered pellets is about 0.12 μm. The maximum conductivity at 20 ℃ is 3.165×10 -5 S·cm -1 for Li 4.4Al 0.4Si 0.6O 4-0.2Li 3BO 3.展开更多
基金supported by the National Key Research and Development Program of China(No.2016YFB0301004)the National Natural Science Foundation of China(No.51771115)+1 种基金the Science and Technology Innovation Project(No.009-031-001)Research Program of Joint Research Center of Advanced Spaceflight Technologies(Nos.USCAST2015-25 and USCAST2016-18)
文摘This study was conducted to discuss the effect of rolling strain on microstructure and tensile properties of dual-phase Mg-8Li-3Al-2Zn-0.5 Y（wt%） alloy, which was prepared by casting, and then homogenized and rolled at 200℃. The rolling process was conducted with 10% reduction per pass and five different accumulated strains, varying from 10% to 70%. The results indicate that the as-cast and as-rolled Mg-8Li-3Al-2Zn-0.5Y alloys are composed of α-Mg, β-Li, AlLi and Al;Y phases. After rolling process,anisotropic microstructure was observed. a-Mg phase got elongated in both rolling direction and transverse direction with the addition of rolling strain. Consequently, the strength of the alloy in both directions was notably improved whereas the elongation declined, mainly caused by strain hardening and dispersion strengthening. The tensile properties of the as-rolled alloys in the RD, no matter the YS, UTS or the elongation, are higher than those of the TD due to their larger deformation strain and significant anisotropy in the hcp α-Mg phase. In addition, the fracture and strengthening mechanism of the tested alloys were also investigated systematically.
文摘The application of all-solid-state Li-metal batteries with solid oxide electrolytes is hindered by interfacial issues,especially the solid electrolyte/Li-metal interface.This work introduced a uniform indium film layer on the surface of Na^(+)super ionic conductor(NASICON)solid electrolyte Li_(1.5)Al_(0.5)Ge_(1.5)P_(3)O_(12)(LAGP),which promotes the intimate contact between Li metal and solid electrolyte and hinders the side reactions at the interface.Electrochemical impedance spectra show that the battery with coated solid electrolyte presents a smaller interfacial resistance and maintains stability after a long cycling time.By contrast,the baseline battery with a pure LAGP pellet shows a contact loss after cycling with the vibration of interfacial impedance.The Li symmetric cells with indium-modified solid electrolyte present stable cycling behavior over 400 h at 0.1 and 0.2 mA·cm^(−2).The all-solid-state Li-metal batteries with a Li anode,indium coating LAGP and two kinds of cathodes,namely carbon nanotubes(CNTs)and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811),are prepared and tested.The CNTs cathode for Li-O2 and Li-air batteries has a higher specific capacity than traditional Li-ion battery cathodes.The Li-NCM811 batteries deliver an initial Coulombic efficiency of about 75%,with 82%capacity retention after 20 cycles.
文摘The Li 4.4Al 0.4Si 0.6O 4-xLi 3BO 3 (x=0 to 0.5) ion conductors were prepared by the sol-gel method. The powder and sintered samples were characterized by DTA-TG, XRD, SEM and ac impedance techniques. The temperature of the preparation of powder patterns decreased by this method as compared to that of the preparation in solid state reaction. The conductivity and sinterability increased with Li 3BO 3 increasing from x=0 to 0.2 in the Li 4.4Al 0.4Si 0.6O 4-xLi 3BO 3 solid electrolytes. The particle size of the sintered pellets is about 0.12 μm. The maximum conductivity at 20 ℃ is 3.165×10 -5 S·cm -1 for Li 4.4Al 0.4Si 0.6O 4-0.2Li 3BO 3.
