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Improving hydrogen embrittlement resistance of a modified press hardening steel by introducing retained austenite as hydrogen trap

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Journal of Iron and Steel Research International 2022年第11期29卷 1864-1872页

作者： Wei Ding Kai Yang Yu Gong Li Wang Ji-yao Hong Wei Li Xue-jun Jin Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiao Tong UniversityShanghai 200240China Institute of Advanced Steels and Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Development and Application Technology of Automotive Steels BaoSteel Research InstituteShanghai 201900China

The effect of retained austenite(RA)with higher mechanical stability on hydrogen embrittlement resistance of a modified 22MnB5(C 0.22,Si 0.8,Mn 1.5,B 0.002,Fe balance,in wt.%)press hardening steel(PHS)has been ***-step quenching and partitioning(Q&P)treatment was applied to PHS,and around 6 vol.%ultra-fine RA was *** ultra-fine RA was found to act as stronger hydrogen trap than dislocations and grain boundaries in martensitic matrix and can decrease the apparent diffusion coefficient of hydrogen from 5.97×10^(-7) to 3.83×10^(-7) cm^(2) s^(-1),which was verified by the combination of thermal desorption spectroscopy analysis and hydrogen permeation *** higher mechanical stability of the ultrafine RA assures enough stability of the hydrogen trap,which results in better hydrogen embrittlement resistance in Q&P-treated PHS than the conventional directly quenched PHS.

关键词： Hydrogen embrittlement Press hardening steel Quenching and partitioning Retained austenite Thermal desorption spectroscopy Hydrogen permeation

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Rational design of hierarchically porous Fe-N-doped carbon as efficient electrocatalyst for oxygen reduction reaction and Zn-air batteries

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Nano Research 2021年第12期14卷 4768-4775页

作者： Zihan Meng Neng Chen Shichang Cai Jiawei Wu Rui Wang Tian Tian Haolin Tang Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan528200China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China School of Material Science and Engineering Henan University of TechnologyZhengzhou450001China

The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/electron transfer under the gas-solid-liquid triple-phase condition. Herein, an ingenious method through the pyrolysis of creative polyvinylimidazole coordination with Zn/Fe salt precursors is developed to fabricate hierarchically porous Fe-N-doped carbon framework as efficient ORR electrocatalyst. The volatilization of Zn species combined with the nanoscale Kirkendall effect of Fe dopants during the pyrolysis build the hierarchical micro-, meso-, and macroporous nanostructure with a high specific surface area (1,586 m^(2)·g^(−1)), which provide sufficient exposed active sites and multiscale mass/charge transport channels. The optimized electrocatalyst exhibits superior ORR activity and robust stability in both alkaline and acidic electrolytes. The Zn-air battery fabricated by such attractive electrocatalyst as air cathode displays a higher peak power density than that of Pt/C-based Zn-air battery, suggesting the great potential of this electrocatalyst for Zn-air batteries.

关键词： hierarchically porous structure Fe-N-doped carbon electrocatalysts oxygen reduction reaction Zn-air batteries

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理论揭示锂硫电池第二放电平台的主要液固相转换机制

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Science China materials 2024年第8期67卷 2683-2693页

作者：张洪毅薛红涛魏承东孙杰许健汤富领 School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of TechnologyLanzhou 730050China

锂硫电池因其高理论能量密度、环境友好和低廉的成本而被认为是前景广阔的新型储能设备,但在放电后半程中缓慢的还原动力学严重阻碍其实际应用.虽然各种先进的正极材料改善了反应动力学,但硫还原反应(SRR)的复杂机理给提高锂硫电池性能... 详细信息

锂硫电池因其高理论能量密度、环境友好和低廉的成本而被认为是前景广阔的新型储能设备,但在放电后半程中缓慢的还原动力学严重阻碍其实际应用.虽然各种先进的正极材料改善了反应动力学,但硫还原反应(SRR)的复杂机理给提高锂硫电池性能设下许多障碍.深入研究其电催化机理是指导阴极材料设计和应用的重要环节.本文将揭示从Li_(2)S_(3);向Li_(2)_(S))(2)/Li_(2)_(S)的转化机制,即揭示从液相多硫化物到固相多硫化物的硫还原反应.以Ti、V、Fe、Co和Ni单原子催化剂为正极催化材料,建立基于密度泛函理论计算的电催化模型.中间产物^(*)LiS、^(*)LiS_(2)被用作预测反应路径、速率决定步骤和过电位的描述因子.这项工作解释了放电后期可溶多硫化物向不溶多硫化物的转化机理,为设计先进的高性能锂硫电池电催化剂提供了指导.

关键词：锂硫电池电催化剂阴极材料储能设备正极材料多硫化物电催化机理密度泛函理论计算

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Influence of the ratio of sintering aids on the properties of porous Si3N4 ceramics fabricated by digital light processing

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Ceramics International 2023年第20期49卷 33004-33010页

作者： Wu, Ya-Ru Tian, Chong Wu, Jia-Min Huang, Hai-Lu Liu, Chun-Lei Lin, Xin Cheng, Li-Jin Shi, Yu-Sheng State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan430074 China Engineering Research Center of Ceramic Materials for Additive Manufacturing Ministry of Education Wuhan430074 China Wenzhou Key Laboratory of Microwave Communication Materials and Devices Wenzhou Advanced Manufacturing Institute of HUST Wenzhou325035 China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Shaanxi Xi'an710072 China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT China Northwestern Polytechnical University Shaanxi Xi'an710072 China School of Mechanical Engineering Hebei University of Technology Tianjin300401 China

The sintering aids play an important role in affecting the properties of porous Si3N4 ceramics. However, there are few researches on the properties of porous Si3N4 ceramics fabricated by digital light processing (DLP) with different ratios of sintering aids. In this paper, porous Si3N4 ceramics with different ratios of sintering aids (Y2O3-Al2O3) were formed by DLP technology. The influence of Y2O3-Al2O3 ratios on the properties of Si3N4 slurry and porous ceramic was studied systematically. The ratio of Y2O3-Al2O3 had little effect on the rheology and cure depth of Si3N4 slurry due to the low addition of sintering aids. The increase of Y2O3-Al2O3 ratio promoted the anisotropic growth of β-Si3N4. When the ratio of Y2O3-Al2O3 was 9:1, the aspect ratio of β grains reached the maximum. As the ratio of Y2O3-Al2O3 powders increased, the linear shrinkage of porous Si3N4 ceramics showed an increasing and then decreasing trend in three directions. When the Y2O3-Al2O3 ratio was 3:7, the shrinkage rate in the length, width and height direction reached the maximum (27.03%, 30.27% and 40.02%, respectively). The bulk density and flexural strength exhibited an initial increase followed by a subsequent decrease, while the porosity showed the opposite trend. When the Y2O3-Al2O3 ratio was 9:1, the porosity reached a maximum of 28.1%. And the bulk density and flexural strength were 2.42 g/cm3 and 421.58 MPa, respectively. This study is of great significance as it lays the experimental foundation in the performance control of porous Si3N4 ceramics fabricated by DLP. © 2023 Elsevier Ltd and Techna Group S.r.l.

关键词： Sintering

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三维分级复合固态电解质用于增强全固态锂金属电池界面相容性

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Science China materials 2023年第2期66卷 522-530页

作者：吴梦君宋江平朱欣欣詹慧田甜王锐雷家珩唐浩林 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Department of Chemistry School of ChemistryChemical Engineering and Life SciencesWuhan University of TechnologyWuhan 430070China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200China

复合固体电解质结合了聚合物固体电解质和无机固态电解质的优势,被认为是用于高能量密度全固态锂金属电池最有前景的电解质.但是,电极/电解质界面相容性差以及填料团聚阻碍了复合固态电解质的实用化进程.为解决上述问题,本文利用硅烷偶... 详细信息

复合固体电解质结合了聚合物固体电解质和无机固态电解质的优势,被认为是用于高能量密度全固态锂金属电池最有前景的电解质.但是,电极/电解质界面相容性差以及填料团聚阻碍了复合固态电解质的实用化进程.为解决上述问题,本文利用硅烷偶联剂(KH570)修饰Li_(6.4)La_(3)Zr_(2)Al_(0.2)O_(12)(KH@LLZO),通过原位聚合得到三维分级结构复合固态电解质.电解质中填料(KH@LLZO)含量高(80 wt%)的一侧提供刚性的屏障来抑制锂枝晶的生长;填料含量低(8 wt%)的一侧具有最优的离子电导率,赋予电池体系高效的锂离子传输.得益于电解质独特的分级结构,采用该电解质组装得到的对称锂电池具有0.9 mA cm^(-2)的临界电流密度,并且在0.3 mA h cm^(-2)的面容量下稳定循环超过600 h.组装的Li|LiFePO_(4)电池也展现了长循环稳定性(0.5 C电流密度下循环200圈,容量保持率为91.6%).此外,组装得到的软包电池表现出优异的柔韧性和安全性.本研究提出的采用表面修饰填料(KH@LLZO)构筑得到的分级结构复合固态电解质,为开发无枝晶、高性能全固态锂金属电池开辟了一条新途径.

关键词：固态电解质临界电流密度聚合物固体电解质分级结构离子电导率锂电池界面相容性复合固体电解质

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高效多孔碳基催化剂的研究进展及其在锌空气电池中应用

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Science China materials 2023年第9期66卷 3381-3400页

作者：蔡世昌安宇冯亚刚段磊张寒露张猛吴佳宾唐浩林 School of Materials Science and Engineering Henan University of TechnologyZhengzhou 450001China Department of Chemistry Tsinghua UniversityBeijing 100084China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong LaboratoryXianhu Hydrogen ValleyFoshan 528200China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

近年来,能源短缺问题日益突出,传统化石燃料使用过程中排放的二氧化碳大大加剧了全球变暖.锌空气电池作为一种新型能源,由于其低成本、高比能量密度、高安全性和环境友好等优点而受到广泛关注.然而,锌空气电池的发展速度缓慢,一个主要... 详细信息

近年来,能源短缺问题日益突出,传统化石燃料使用过程中排放的二氧化碳大大加剧了全球变暖.锌空气电池作为一种新型能源,由于其低成本、高比能量密度、高安全性和环境友好等优点而受到广泛关注.然而,锌空气电池的发展速度缓慢,一个主要原因是阴极空气催化剂的催化效率低和稳定性差.本文总结了用于空气阴极的多孔碳基催化剂的最新研究进展.在对锌空气电池进行简要介绍后,从孔结构和杂原子掺杂两方面介绍了碳载体的结构和组成.根据孔径大小:微孔、介孔和大孔,详细介绍了锌空气电池中多孔碳的设计和制备.此外,还根据氮、氟、硫、磷和硼等杂原子类别,分别讨论了杂原子掺杂的合成策略以及相应电池性能.最后,本文对锌空气电池未来发展过程中的挑战和机遇进行了展望.

关键词：锌空气电池碳载体能源短缺问题碳基催化剂化石燃料杂原子掺杂多孔碳新型能源

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Trace of Atomically Dispersed Pd Enables Unprecedented Butadiene Semihydrogenation Performance Over Copper Catalyst

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ACS Catalysis 2025年第5期15卷 3810-3822页

作者： Zhao Wang Hao Yuan Jian Tao Shu-Lin Liu Ying Hong Zhi-Yi Hu Jian Zhang Bao-Lian Su The State Key Laboratory of Advanced Technology for Material Synthesis and Processing Wuhan University of Technology Wuhan Hubei 430070 P. R. China State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Xi’an Shaanxi 710000 P. R. China The State Key Laboratory of Advanced Technology for Material Synthesis and Processing Wuhan University of Technology Wuhan Hubei 430070 P. R. China；Laboratory of Inorganic Materials Chemistry (CMI) University of Namur 61 rue de Bruxelles Namur B-5000 Belgium

Semihydrogenation plays a key role in industrial hydrorefining of light alkenes, with a market above 400 billion by 2027. The high cost of commercial palladium-based catalysts strongly calls for innovation but with great challenges. Herein, copper nanoparticles decorated with a minimized ppm of Pd are developed through a chemical plating process to integrate the catalytic advantages of copper and palladium for achieving maximized catalysis in the semihydrogenation of a fatal impurity of butadiene in alkene feedstocks. The developed Pd–Cu catalyst (i.e., 114 ppm of Pd in Pd0.0033Cu1/TiO2) exhibits an unprecedented catalytic performance superior to commercial Pd/Al2O3, with 100% butene selectivity above 90% of butadiene conversion over 130 h on stream at 90 °C. Further exploration reveals that the atomically dispersed Pd on Cu nanoparticles, obtained at ultralow ppm levels of Pd loading, induces a hidden but critical H2trap, which concentrates H2on the Pd site for further H2dissociation that offers intermediate hydrogen atoms to the tandem butadiene semihydrogenation over the third layer of Cu atoms neighboring Pd through hydrogen spillover. Moreover, a threshold on Pd density was identified at Pd/Cu surficial atomic ratio of 1/138 (i.e., Pd0.0033Cu1/TiO2) for maximizing butadiene semihydrogenation performance, based on an extreme collaboration between Pd for H2dissociation and Cu for butadiene hydrogenation. This work provides important guidance for developing noble metal-saving catalysts in industrial applications.

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Understanding the creep behaviors and mechanisms of Mg-Gd-Zn alloys via machine learning

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Journal of Magnesium and Alloys 2024年第8期12卷 3281-3291页

作者： Shuxia Ouyang Xiaobing Hu Qingfeng Wu Jeong Ah Lee Jae Heung Lee Chenjin Zhang Chunhui Wang Hyoung Seop Kim Guangyu Yang Wanqi Jie Graduate Institute of Ferrous and Eco Materials Technology(GIFT) Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Xi’an Rare Metal Materials lnstitute Co.Ltd Xi’an 710016China Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea DepartmentAdvanced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai 980-8577Japan Institute for Convergence Research and Education in Advanced Technology Yonsei UniversitySeoul 03722South Korea

Mg-Gd-Zn based alloys have better creep resistance than other Mg alloys and attract more attention at elevated ***,the multiple alloying elements and various heat treatment conditions,combined with complex microstructural evolution during creep tests,bring great challenges in understanding and predicting creep *** this study,we proposed to predict the creep properties and reveal the creep mechanisms of Mg-Gd-Zn based alloys by machine *** the one hand,the minimum creep rates were effectively predicted by using a support vector regression *** complex and nonmonotonic effects of test temperature,test stress,alloying elements,and heat treatment conditions on the creep properties were *** the other hand,the creep stress exponents and creep activation energies were calculated by machine learning to analyze the variation of creep mechanisms,based on which the constitutive equations of Mg-Gd-Zn based alloys were *** study introduces an efficient method to comprehend creep behaviors through machine learning,offering valuable insights for the future design and selection of Mg alloys.

关键词： Mg-Gd-Zn based alloys Machine learning Creep rate Creep mechanism Constitutive equation

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Processable Potassium Metal Anode for Stable Batteries

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Energy & Environmental materials 2022年第4期5卷 1278-1284页

作者： Zhenghang Wei Aoxuan Wang Xuze Guan Guojie Li Zhiwei Yang Chengde Huang Jing Zhang Libin Ren Jiayan Luo Xingjiang Liu Key Laboratory for Green Chemical Technology of Ministry of Education State Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Key Laboratory of Materials Processing and Mold Zhengzhou UniversityMinistry of EducationZhengzhou 450002China Jiangxi Key Laboratory of Nanobiomaterials Institute of Advanced MaterialsEast China Jiaotong UniversityNanchang 330013China National Key Laboratory of Science and Technology on Power Sources Tianjin Institute of Power SourcesTianjin 300384China Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The future of high-energy density electrochemical energy storage systems relies on the advancement of rechargeable batteries that utilize reactive metals as *** the alkaline metal,secondary battery systems because of abundant resource,high capacity and low redox potential,potassium(K)metal secondary battery(KMB)is expected to replace the existing lithiumion battery as a versatile platform for high-energy density,cost-effective energy storage ***,the difficulty in processing metal K results in nonstandard electrodes and hinders the development of ***,the mobility of the K metal anode due to its unique lowmelting point character at elevated temperatures in practical conditions leads to severe instability and risks in chemical/electrochemical ***,we fabricate a processable and moldable composite K metal anode by encapsulating K into reduced graphene oxide(rGO).The composite electrode can be engineered into various shapes discretionarily with precise sizes and stabilize the K metal anode at relatively high ***,the composite anode exhibits excellent cycling performance at high current density(8 mA cm^(-2)) with dendrite-free *** with a Prussian blue cathode,the rGO-K composite anode shows much improved electrochemical performance and extended lifetime.

关键词： K metal anode K metal battery processibility reduced graphene oxide stability

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Three‑Dimensional Numerical Study on the Metal Rotating Spray Transfer Process of High‑Current GMAW

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 234-246页

作者： Lei Xiao Ding Fan Jiankang Huang School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China State Key Laboratory of Advanced Processing and Recycling of Non‑ferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

A three-dimensional numerical model based on the volume-of-fluid(VOF)method is typically preferred for studying high-current gas metal arc welding(GMAW)metal transfer mechanism and then controlling *** is informed that the rotating spray transfer is extremely complicated,and some researchers have focused on simplified models without considering the energy conservation to make analysis manageable for the unstable metal transfer *** our created numerical model,the metal transfer of high-current GMAW with shielding gas of different conductivities has been studied by analyzing acting forces and fluid flows in the metal liquid column,especially for the contributions of the self-induced electromagnetic force,equivalent volume force of the capillary pressure of the surface tension(Named surface tension force in this work),static arc *** is found that the unbalanced electromagnetic force greatly promotes the metal rotating motion in 500 A metal inert gas(MIG)welding with pure argon shielding gas and it pushes the metal liquid column to *** the arc constricting effect in active shielding gas by simply changing the arc conductivity,it is found that the metal liquid column no longer rotates,it turns to swing since the unbalanced electromagnetic force is large enough to break the rotating *** calculated results of the metal liquid column deflected angle and rotating/swing frequency agree well with the experiment of high-speed camera observations.

关键词： Gas metal arc welding Rotating spray transfer Three-dimensional model Electromagnetic force Surface tension

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