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Compared with conventional isothermal creep aging (ICA), non‐ICA (NICA) does not involve a prolonged holding stage, but only has heating and cooling stages. During the NICA process, the precipitates nucleate and grow up in the early part of heating stage, resulting in fluctuations in creep rate and an increase in strength. The coarsening of precipitates in the later part of the heating stage can lead to significant increase of creep rate. Upon approaching the peak temperature, the dissolution of the precipitates occurs in conjunction with a partial coarsening of the remaining precipitates, causing a reduction in strength. However, the secondary precipitation during the cooling stage facilitates a significant strength enhancement in a relatively shorter period. In contrast to the ICA, the targeted NICA treatment gives an increase in ultimate strength while improves the stress corrosion cracking resistance. Moreover, the time required for NICA to obtain ultimate strength is only 13.9% of that of the ICA treatment. A large amount of creep strain can be generated during the NICA process, which is equivalent to 630% of that of creep age forming treatment. [ABSTRACT FROM AUTHOR]

The effect of the heating/cooling rates of nonisothermal aging (NIA) on microstructure and mechanical properties of 2050 Al–Li alloy are investigated. The 2050 Al–Li alloy is first solid solutioned and predeformed and then heated from 130 to 220 °C at different rates of 20, 30 °C h−1, or 40 °C h−1 and then cooled to 150 °C. The results show that the mechanical properties of the alloy subjected to NIA treatment can be improved by adjusting the heating and cooling rate. When the heating and cooling rate is 30 °C h−1, the alloy achieves the best mechanical properties; the hardness, ultimate tensile strength (UTS), yield strength (YS), and elongation are 182.9 HV, 597, 571 MPa, and 9.6%, respectively. With the decrease of heating (or cooling) rate of NIA, the diameter and thickness of the T1 precipitate increase and the volume fraction decreases, resulting in the variation in mechanical properties. Therefore, herein, premier precipitation behavior and improved mechanical properties are both achieved by modifying the heating and cooling rate of NIA; the effect of the heating/cooling rate of NIA on the microstructure evolution of 2050 Al–Li alloy is revealed, and the underlying strengthening mechanism is investigated in detail. [ABSTRACT FROM AUTHOR]

Liquid‐phase sintering (LPS) is an effective pathway to assist the densification of ceramics. However, it has seldom been used to densify glass–ceramics. In the present study, a multielement co‐doping strategy has been utilized to achieve LPS of a ZrO2–SiO2 nanocrystalline glass–ceramic. Compared with undoped samples densified by solid‐state sintering, doping of equimolar Al, Y, and Ca promoted the densification of the glass–ceramic at lower temperatures with a faster densification rate. Ternary doping enhanced coarsening of ZrO2 nanocrystallites during sintering and annealing. The distribution of dopants was carefully observed with X‐ray energy‐dispersive spectrometry technique in scanning electron transmission microscopy mode. Results showed that the three dopants showed different distribution behaviors. After sintering, Y dopants were predominately distributed in ZrO2 nanocrystallites, whereas parts of Al and Ca dopants were distributed in ZrO2 nanocrystallites and part of them co‐segregated at the ZrO2/SiO2 heterointerfaces. Meanwhile, the segregation of Ca dopant at some intergranular films among ZrO2 nanocrystallites was observed. Redistribution of dopants did not occur during annealing. [ABSTRACT FROM AUTHOR]

It remains challenging to achieve further breakthroughs in the development of durable bifunctional air cathode electrocatalysts for increasing the cycling life of rechargeable Zn‐air battery (RZAB). Herein, d‐band gap narrowing strategy is proposed to significantly boost the electrocatalytic activity and stability of spinel Co3O4 for both oxygen reduction and evolution reactions. In situ Raman spectroscopy finds that the Ce atom substitution can significantly improve the durability and corrosion resistance of electrocatalysts in harsh alkaline electrolytes. Synchrotron X‐ray absorption fine structure reveals that the Co3+/Co2+ ratio of Co3O4 can be tuned with Ce introduction, which is beneficial to optimize the adsorption/desorption of the intermediates over Cooh3+ active sites. Density functional theory calculations further confirm the reduced gap between Co d‐band and O p‐band centers, increased electrical conductivity, together with the deepened valence band maximum of Co sites in Ce‐doped Co3O4. Thereby, the optimized RZAB with Ce‐Co3O4 delivers excellent long‐term durability (290 h) and large specific capacity (876.3 Wh kgZn−1$Wh\;kg_{Zn}^{{\bm{ - }}1}$), which possesses great prospects in all‐solid‐state flexible RZAB devices. [ABSTRACT FROM AUTHOR]

The rampant dendrites and hydrogen evolution reaction (HER) resulting from the turbulent interfacial evolution at the anode/electrolyte are the main culprits of short lifespan and low Coulombic efficiency of Zn metal batteries. In this work, a versatile protective coating with excellent zincophilic and amphoteric features is constructed on the surface of Zn metal (ZP@Zn) as dendrite‐free anodes. This kind of protective coating possesses the advantages of reversible proton storage and rapid desolvation kinetics, thereby mitigating the HER and facilitating homogeneous nucleation concomitantly. Furthermore, the space charge polarization effect promotes charge redistribution to achieve uniform Zn deposition. Accordingly, the ZP@Zn symmetric cell manifests excellent reversibility at an ultrahigh cumulative plating capacity of 4700 mAh cm−2 and stable cycling at 80 % depth of discharge (DOD). The ZP@Zn//V6O13 pouch cell also reveals superior cycling stability with a high capacity of 326.6 mAh g−1. [ABSTRACT FROM AUTHOR]