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As the turbine inlet temperatures of aero engines continue to rise， there is an urgent need to develop a new generation of single-crystal superalloys and their thermal protective coatings for turbine blades. In order to meet the stringent requirements for the comprehensive performance of high-temperature structural materials in the complex service environments of aero engines， the intelligent design research of single crystal superalloys and thermal protection coatings has been gradually carried out at home and abroad in recent years under the promotion of material integrated computational engineering and material informatics. This paper reviews the latest research progress in the design of novel single-crystal superalloys and thermal protective coatings by utilizing multi-scale computational simulations and machine learning methods. The findings confirm that multi-scale computational simulations offer robust theoretical support for understanding the strengthening and toughening mechanisms of single-crystal superalloys， as well as the oxidation resistance and diffusion protective mechanisms of thermal protective coatings. Additionally， the study highlights the reliability and significant potential of machine learning in constructing intrinsic "composition-structure-property" relationship for high-temperature structural materials. This approach paves an intelligent and efficient new pathway for the rapid development of next-generation high-temperature single-crystal superalloys and thermal protective coatings.

With the global energy transition and increasing environmental requirements，hydrogen-mixed gas turbines as a high-efficiency and low-emission energy conversion equipment has been widely concerned. This paper reviews the development status of hydrogen-mixed gas turbines domestically and internationally，analyzes the characteristics of hydrogen combustion in gas turbines，explores the impact of hydrogen combustion on complex components and the application of high-temperature materials，and analyzes the performance requirements for hot-end component materials operating under high temperature，high pressure，and corrosive conditions，as well as the main challenges and potential solutions in current material development. The effects of water vapor and hydrogen embrittlement during hydrogen combustion on gas turbine alloys and thermal barrier coatings are discussed in detail.Water vapor accelerates the oxidation and corrosion of alloys，leading to a decline in mechanical properties. Furthermore，hydrogen embrittlement significantly affects the toughness and durability of alloys，increasing the risk of crack propagation and fracture. In terms of the problems，future research should focus on multi-field coupling simulations and accelerated corrosion tests，considering the factors such as temperature，pressure，and different atmospheres to establish realistic environment simulators to evaluate alloy and coating performances. Additionally，the combined effects of hydrogen and water vapor on high-temperature alloys and thermal barrier coatings should be emphasized. This includes investigating the diffusion mechanisms of hydrogen in alloys，interactions with lattice defects，and the microscopic processes leading to hydrogen embrittlement. Building oxidation models in high-temperature water vapor environments，clarifying the dissociation and adsorption mechanisms of water vapor at high temperatures，the hydroxylation of protective oxide films Al2O3 and Cr2O3，and the growth behavior of non-protective oxides（e.g.，spinel） are also essential.

The thin-wall effect of single crystal superalloys refers to the phenomenon that when the thickness of the sample and the part is less than 1 mm，the lasting life is reduced， the creep rate is increased and other mechanical properties are significantly attenuated. With the development of the internal cooling structure of advanced aero-engine single crystal blade parts， the structural thickness of some areas decreases， making it a typical thin-walled structure. Thus， it is of great engineering significance to consider the thin-wall effect in the thin-wall region during the design and manufacture of blades. Creep performance is one of the most important properties of superalloys for turbine blade application. This paper summarizes the thin-wall effect in creep performance of the superalloys as well as some advanced experimental equipment in the study of thin-wall effect. Research on thin-wall debit effect of superalloys can be divided into two categories，one is the cause of thin-wall debit，including the relative enhancement of oxidation，more significance in anisotropy，changes in microstructure and the initiation or growth of defects，and the factors that influence the thin-wall debit effect including experimental conditions（temperature，stress，etc.），the processing methods（casting， machining）， geometric shape （rectangular cross-section， ring cross-section， film cooling holes）. Research on thin-wall debit effect is within the scope of engineering application，as a part of “component level/analog component level” in “building block” verification and evaluation technology，thin-wall debit effect research under service environment or near-service environment conditions is more valuable for application. For this purpose，a variety of advanced experimental equipment platforms have been developed to simulate one or several coupled service conditions（high temperature，high pressure，corrosion/erosion，centrifugal loading） of the blade in the engine. Future research on thin-wall effects should be carried out under conditions closer to actual service conditions by preparing specimens according to the actual blade manufacturing process and conducting experiments on the equipment that simulates the service environment.

The aircraft engine is considered the “heart” of the aircraft. The development of advanced aircraft engines focuses on achieving a high thrust-to-weight ratio，high efficiency，low fuel consumption，and extended operational life. High-temperature functional coatings，such as thermal barrier coatings（TBCs），thermal/environmental barrier composite coatings（T/EBCs），and high-temperature stealth coatings，are applied to critical hot-end components of aircraft engines. These coatings play a significant role in enhancing the service performance，operational life，safety and reliability of the engine. Taking TBCs，T/EBCs，and high-temperature stealth coatings as examples，this paper provides a systematic overview of recent research progress in the design of high-temperature functional coating materials，coating preparation science and technology，and coating performance evaluation and characterization，both domestically and internationally，with a specific focus on the advancements made at Beihang University. Furthermore，challenges and development trends faced by new high-temperature functional coatings of advanced aircraft engines in the future are also discussed. In the future，the research focus of advanced high-temperature functional coatings will shift toward multifunctional composite coatings，enhanced adaptability to extreme environments，and improved process compatibility.

Melting point depressants (MPDs) are required to lower the melting point of filler for brazing. In this study, Zr was used as the MPD, and powder filler was prepared by adjusting the Zr and Mo content referring to Thermo-Calc calculations. The prepared filler was used to braze a high-Mo Ni3Al-based single crystal superalloy, IC21, for 1200 °C/30 min. The effects of adjusting the Zr and Mo content on the microstructure and tensile properties of the joint were investigated. The increase in Zr content promotes the formation of Ni7Zr2 in the joint, leading to a decrease in the tensile strength of the joint. The increase in Mo content forms diffusion barriers between the BM and filler, resulting in an enhancement in the tensile strength of the joint. However, continued increases in Mo content leads to an increase in the P-topologically close packed phase, causing a decline in the tensile strength of the joint. When the Zr content was (11.8–12.2) wt.% and the Mo content was (7.3–7.7) wt.%, the tensile strength of the joint at 980 °C reached a maximum of 550 MPa. This study provides a potential direction for the design of brazing filler composition for high-Mo Ni3Al-based superalloys. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of apoptotic bodies (ABs) derived from dental pulp stem cells (DPSCs) on macrophage polarization and inflammation response in vivo. Methods Human DPSCs were extracted, cultured and identified. Staurosporine was used to apoptosis induction and differential methods were performed for ABs identification. The in vitro cultured macrophages were divided into 3 groups: solvent control, lipopolysaccharide (LPS), and the LPS+ABs. The macrophages were stimulated with LPS to induce inflammation followed by ABs treatment. In the untreated group, macrophages were added with an equal amount of solvent. The specific uptake of ABs by macrophages, the expression level of CD206 and the levels of inflammatory cytokines were analyzed. The mouse models of cutaneous wounds and dextran sulfate sodium (DSS)-induced colitis were established, and the mice were randomly divided into 3 groups: the PBS-treated group, the DPSCs-treated group, and the ABs-treated group. The mice were injected with the same volume of PBS, DPSCs and ABs, respectively. The body weight, histological pathology, the expression levels of CD206 and cytokines, and the extent of tissue regeneration were measured. Results DPSCs and ABs derived from DPSCs were successfully isolated and characterized. ABs could be taken up by macrophage. While lipopolysaccharide(LPS) induced production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), ABs significantly reduced the levels of these pro-inflammatory cytokines and increased the expression of transforming growth factor-β (TGF-β) and CD206 (P < 0.01). In the cutaneous inflammatory wound model, the wound closure rate in mice intravenously injected with ABs was significantly accelerated (P < 0.05). The administration of ABs markedly reduced the pro-inflammatory factors levels and increased the CD206+ cell number. In the colitis model, treatment with ABs markedly reduced the loss in bodyweight (P < 0.05), recovered the colon length (P < 0.01), and significantly increased the CD206+ cell number. Conclusion DPSCs-derived ABs could enhance macrophage M2 polarization and attenuate inflammation. Therefore, ABs could be used as a promising cell replacement for inflammatory regulation and tissue regeneration.