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Microstructure and Wear Resistance of Alcocrfeni-Wc/Tic Composite Coating by Laser Cladding

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SSRN 2022年

作者： Li, Yutao Fu, Hanguang Ma, Tiejun Wang, Kaiming Yang, Xiaojun Lin, Jian Key Laboratory of Advanced Functional Materials Ministry of Education Institute of Welding and Surface Technology Beijing University of Technology Beijing100124 China College of Automobile and Mechanical Engineering Changsha University of Science and Technology Changsha China

AlCoCrFeNi has excellent mechanical properties, however, its hardness and wear resistance are insufficient for engineering applications. In this work, the WC and in-situ TiC particles were used to enhance the wear resistance of AlCoCrFeNi coating. The microstructure, hardness, and wear resistance were studied in detail. The results showed that the in-situ TiC particles were uniformly distributed in the whole coating, ameliorating the uneven distribution of WC particles. A sound interface was formed between the particles and the coating matrix, proving the composite coating performed well in wear resistance. The phase constituents of the coating matrix were the BCC and B2 phases. The dissolution of W atoms led to an increase in the lattice constants of the BCC phase, resulting in strong solid solution strengthening of the coating matrix. Furthermore, a needle W-rich BCC phase appeared in the coating matrix with the increase of WC content. As a result, the hardness of AlCoCrFeNi-WC/TiC coatings increased from 516.4 HV0.3 to 808.7 HV0.3, and the wear resistance was increased by 14 times. Therefore, the improvement in hardness can be attributed to the WC particles, in-situ TiC particles, and solid-solution strengthening. © 2022, The Authors. All rights reserved.

关键词： Wear resistance

Effect of Aging on surface Strengthened Layer and High-Temperature Low-Cycle Fatigue Property of Cold-Expanded Hole Structure

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SSRN 2023年

作者： Xu, Chunling Wang, Xin Hu, Bo Yu, Bo Luo, Xuekun Hu, Rengao Cui, Haitao Hu, Dianyin Zheng, Haizhong Tang, Zhihui Gu, Yuanxing Surface Engineering Institution AECC Beijing Institute of Aeronautical Materials Beijing100095 China Aviation Key Laboratory of Advanced Corrosion and Protection on Aviation Materials AECC Beijing Institute of Aeronautical Materials Beijing100095 China School of Material Science and Engineering Nanchang Hangkong University Nanchang330063 China AECC Sichuan Gas Turbine Establishment Chengdu610500 China Research Institute of Aero-Engine Beihang University Beijing100191 China Beijing Key Laboratory of Aero-Engine Structure and Strength Beijing100191 China

A surface-strengthened layer formed by cold expansion (CX) at room temperature evolves at high temperatures. The evolution of surface roughness, residual stress profile, microhardness gradient, and microstructure after CX treatment of a center-hole plate prepared from a GH4169 superalloy, have been investigated in the present study. The aging took place at a temperature of 400 ℃ and 600 ℃, and for the duration of 500 h (CX+400℃/500h and CX+600℃/500h). Furthermore, the influence of the evolution of properties presented above, on the low cycle fatigue properties at 820MPa/600℃/R=0.1, has also been studied. The results show that the average surface roughness has become reduced by 59.2% to Ra0.167 μm as a result of CX, and as compared with the corresponding results after reaming. In addition, the roughness after aging has been slightly improved. Also, as a result of CX treatment, the depth of the compressive residual stress has become larger than 1.4 mm, with a prominent relaxation taking place in the first five hours of aging (at 400 ℃ or 600 ℃). However, the CX treatment was not found to affect the surface hardness. After aging at 600 ℃, a transformation from γ’’ phase to δ phase could be observed in the TEM images, which did not occur for aging at 400 ℃. The theoretical expectation of the fatigue lives of the as-received sample was 7015 cycles at 820MPa/600℃. This fatigue gain after CX treatment and CX+400℃/500h, were 5.27 times and 2.86 times higher respectively, indicating a fatigue life reduction of thermal aging compared with CX treatment. Furthermore, the fatigue life of the original sample was reduced to 5576 cycles after aging at 600 ℃, while the corresponding fatigue life of the CX-treated sample was 7979 cycles. It is obviously that after aging at 600 ℃, the fatigue life of CX treated sample is significantly shortened, but still 43.1% higher than that of the comparison group without CX treatment. The analysis showed that the relaxation of the strengthening l

关键词： surface roughness

Anthradithiophene based hole-transport material for efficient and stable perovskite solar cells

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Journal of Energy Chemistry 2020年第9期29卷 293-298,I0009页

作者： Guohua Wu Yaohong Zhang Ryuji Kaneko Yoshiyuki Kojima Ashraful Islam Kosuke Sugawa Joe Otsuki Shengzhong Liu Key Laboratory of Applied Surface and Colloid Chemistry National Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Laboratory for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710119China College of Science and Technology Nihon UniversityChiyoda-ku101-8308 TokyoJapan Department of Engineering Science Faculty of Informatics and EngineeringThe University of Electro-CommunicationsChofu182-8585 TokyoJapan Photovoltaic Materials Group National Institute for Materials Science(NIMS)Tsukuba 305-0047Japan

A novel hole-transport material(HTM)based on an anthradithiophene central bridge named BTPA-7 is *** comparison to spiro-OMeTAD(2,2’,7,7’-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9’-spirobifluorene),the synthetic steps of BTPA-7 are greatly reduced from 6 to 3 and the synthetic cost of BTPA-7 is nearly a half that of ***,BTPA-7 exhibits a relatively lower conductivity but higher hole mobility and higher glass transition temperature(Tg)than *** with the photovolatic performance for spiro-OMeTAD,FA0.85MA0.15PbI3 and MAPbI3 PSC devices based on BTPA-7 exhibit slightly lower PCEs with the values of 17.58%(18.88%for spiro-OMeTAD)and 11.90%(13.25%for spiro-OMeTAD),***,a dramatically higher JSC of PSC based on BTPA-7is achieved,which arises from the higher hole mobility of *** addition,the relatively hydrophobic character of BTPA-7 eventually enhances the PSC device *** cost,higher hole mobility,higher Tg,satisfactory photovoltaic performance,and superior device stability of BTPA-7 can be utilized as a substitute for spiro-OMeTAD in PSCs.

关键词： Anthradithiophene Hole-transport material Stability Synthetic cost

Electrically Conductive and Flame Retardant Graphene/Brominated Polystyrene/Maleic Anhydride Grafted High Density Polyethylene Nanocomposites with Satisfactory Mechanical Properties

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Chinese Journal of Polymer Science 2019年第5期37卷 509-517页

作者： Yu Chen Jian Yao Ming-Ke Xu Zhi-Guo Jiang Hao-Bin Zhang National Key Laboratory of Advanced Composites Beijing Institute of Aeronautical Materials Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical Technology

Electrically conductive and flame-retardant maleic anhydride grafted high-density polyethylene(MA-HDPE) nanocomposites with satisfactory mechanical properties are fabricated by melt compounding MA-HDPE with polyethyleneimine(PEI)-modified reduced graphene oxide(PEI@RGO) as the conductive nanofiller and brominated polystyrene(BPS) as the flame retardant. The modification with PEI significantly improves the interfacial compatibility and dispersion of the RGO sheets in the MA-HDPE matrix, leading to electrically conductive nanocomposites with enhanced mechanical properties. Furthermore, the addition of 25 wt% of BPS makes the nanocomposite flame-retardant with a UL-94 V-0 rating. Thus, the multifunctional RGO/MA-HDPE nanocomposites with good electrical, flameretardant, and mechanical properties would have potential applications in construction and pipeline fields.

关键词： Polymer nanocomposites High density polyethylene Graphene Electrical conductivity Flame retardancy

Sodium Storage Properties of Fe, Ni-Bimetallic Doped Carbon-Modified Nati2(Po4)3

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SSRN 2024年

作者： Che, Junling Yu, Jiaojiao Xu, Tong Yu, Kang Qin, Jian Ma, Junchao Ren, Wei Li, Xifei Xi’an Key Laboratory of New Energy Materials and Devices China Shaanxi International Joint Research Center of Surface Technology for Energy Storage Materials China School of Science Xi'an University of Posts and Telecommunications Shaanxi Xi’an710121 China Institute of Advanced Electrochemical Energy School of Materials Science and Engineering Xi'an University of Technology Xi’an710048 China

NaTi2(PO4)3 (NTP), possessing a sodium superionic conductor (NASICON) structure, is considered an attractive anode material for aqueous sodium ion batteries (ASIBs) due to its three-dimensional open framework and appropriate negative voltage window. However, the intrinsically poor electrical conductivity of NTP hampers its application in ASIBs. Herein, bimetallic doped carbon material was designed and combined with the sol-gel method to synthesize NaTi2(PO4)3-C-FeNi (NTP-C-FeNi) composite materials. This bimetallic doped carbon composite NTP material not only effectively improves conductivity, but also enlarges the contact area with the electrolyte, facilitating the rapid migration of Na+. Following the rate performance test, NTP-C-FeNi retained a reversible capacity of 116.75 mAh⋅g-1 at a small current density of 0.1 A⋅g-1, representing 95.9% of the initial capacity. After 500 cycles at a high current density of 1.5 A⋅g-1, the cycle stability was 85.3%. The improvement in electrochemical performance may be attributed to the widening of pathways and acceleration of Na+ insertion/extraction facilitated by FeNi-C doping, while the carbon coating effectively promotes electrode charge transfer. The results indicate that the bimetallic doped carbon composite NaTi2(PO4)3 holds potential for practical applications in novel aqueous sodium ion battery systems. © 2024, The Authors. All rights reserved.

关键词： Sodium-ion batteries

Sandwiching Sulfur into the Dents Between N,O Co-Doped Graphene Layered Blocks with Strong Physicochemical Confinements for Stable and High-Rate Li-S Batteries

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Nano-Micro Letters 2020年第11期12卷 13-24页

作者： Mengjiao Shi Su Zhang Yuting Jiang Zimu Jiang Longhai Zhang Jin Chang Tong Wei Zhuangjun Fan Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China Key Laboratory of Energy Materials Chemistry Ministry of EducationKey Laboratory of Advanced Functional MaterialsAutonomous RegionInstitute of Applied ChemistryXinjiang UniversityUrumqi 830046People’s Republic of China State Key Laboratory of Heavy Oil Processing School of Materials Science and EngineeringChina University of PetroleumQingdao 266580People’s Republic of China

The development of lithium-sulfur batteries(LSBs)is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle ***,an N,O co-doped graphene layered block(NOGB)with many dents on the graphene sheets is designed as effective sulfur host for high-performance LSB *** sulfur platelets are physically confined into the dents and closely contacted with the graphene scaffold,ensuring structural stability and high *** highly doped N and O atoms can prevent the shuttle effect of sulfur species by strong chemical ***,the micropores on the graphene sheets enable fast Li^+transport through the *** a result,the obtained NOGB/S composite with 76 wt%sulfur content shows a high capacity of 1413 mAh g^-1 at 0.1 C,good rate performance of 433 mAh g^-1 at 10 C,and remarkable stability with 526 mAh g^-1 at after 1000 cycles at 1 C(average decay rate:0.038%per cycle).Our design provides a comprehensive route for simultaneously improving the conductivity,ion transport kinetics,and preventing the shuttle effect in LSBs.

关键词： Graphene Physicochemical confinement Cycle stability Shuttle effect Li-S batteries

Hollow Nanoparticles Doped Hierarchical Hexagonal Star Shaped Cobalt-Based Phosphosulfides for Water Splitting

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SSRN 2023年

作者： Liang, Zuozhong Zhang, Jieling Suo, Weiran Zheng, Haoquan Wang, Yuan Cao, Rui Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education School of Chemistry and Chemical Engineering Shaanxi Normal University Xi’an710119 China School of Advanced Materials and Nanotechnology Xidian University Xi’an710126 China Southern University of Science and Technology China

Hollow nanoparticles doped hierarchical hexagonal star shaped cobalt (Co) phosphosulfides (CoS/P) have been prepared with sulphidation and phosphorization of Co-based hydroxides as precursors sequentially. Each corner of a hexagonal star is composed of many branched nanorods. Hollow nanoparticles with an average size of 50 nm are observed on these branches. The resulting CoS/P catalyst show efficient water splitting activity. These hollow nanoparticles provide more exposed active sites with enhanced reaction activity and reaction rate. Theoretical calculations also confirm the beneficial effect of CoS/P compared with CoS. This novel hierarchical structure is a promising electrocatalyst for overall water splitting. © 2023, The Authors. All rights reserved.

关键词： Cobalt compounds

Corrigendum to ‘Correlating multi-scale structure characteristics to mechanical behavior of Caprinae horn sheaths’

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Journal of Materials Research and technology 2023年 24卷 10056-10057页

作者： Kang Yang Nannan Qin Haiyun Yu Changgeng Zhou Hailiang Deng Wenhan Tian Siyu Cai Zihong Wu Juan Guan Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials (Anhui University of Technology) Ministry of Education Maanshan 243002 China School of Materials Science and Engineering Anhui University of Technology Maanshan 243002 China State Key Laboratory of Molecular Engineering of Polymers (Fudan University) Shanghai 200433 China Composite Component Technology Center Aviation Industry Corporation of China (AVIC) Composite Corporation Ltd Beijing 101300 China International Research Center for Advanced Structural and Biomaterials School of Materials Science and Engineering Beihang University Beijing 100191 China Guiyang Engine Research Institute of Aviation Industry Corporation of China(AVIC) Guiyang 550081 China

Enhanced Cycling Stability of F-Doped Na4Fe3(PO4)2P2O7 Cathode Material for Sodium-Ion Batteries

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SSRN 2024年

作者： Cao, Yanyan Ma, Yongtao Yang, Zihao Xie, Xiangyang Huang, Wei Liu, Dongzhu Wang, Jiangtao Qin, Jian Li, Ming Wang, Jingjing Li, Wenbin Su, Yaqiong Li, Xifei Institute of Advanced Electrochemical Energy School of Materials Science and Engineering Xi'an University of Technology Shaanxi Xi’an710048 China for Industry-Education Integration of Energy Storage Technology Xi’an Jiaotong University Xi’an710049 China Shaanxi International Joint Research Center of Surface Technology for Energy Storage Materials China Xi’an Key Laboratory of New Energy Materials and Devices China

Efficient and durable cathode materials are crucial for improving the performance and reliability of sodium ion batteries (SIBs) in various energy storage applications. This study explores the complex mechanism of enhancing electrochemical performance of F-doped Na4Fe3(PO4)2P2O7 (NFPP) by combining density functional theory (DFT) and experiments, with a focus on improving electronic conductivity and cycling stability. Detailed explanation was given on the reasons why Na2 cannot be extracted due to its large coordination number and unique structure. The migration of sodium ions in NFPP is 1D and 2D, rather than the commonly believed 3D, mainly because the c-direction channel is blocked by Na2 that cannot be released. The NFPP and NFPP/F electrodes initial capacity at 1C was 95.7 and 105.9 mAh g−1, and remained at the initial capacity (70.2%) and (86.2%) after 1000 cycles. The results reveal that F doping can greatly improve the cyclic stability of NFPP materials, which is attributed to the change in the twisting mode of two P2O7 dimers during sodium extraction/insertion process. These findings contribute to ongoing research efforts aimed at developing high-performance NFPP sodium ion batteries, thus facilitating the practical application in sustainable energy storage systems. © 2024, The Authors. All rights reserved.

关键词： Cathodes