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Chinese Journal of Polymer science 2024年第8期42卷 1085-1092页

作者： Hong-Yu Ji Hong-Liang Mu Chun-Feng tang Yu-Xing Zhang Yue Chi Zhong-Bao Jian key laboratory of advanced structural materials Ministry of EducationSchool of Materials Science and EngineeringChangchun University of TechnologyChangchun 130012China State key laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Olefin polymerization is one of the most im portant chemical reactions in *** work presents a strategy that emphasizes the synergistic meta/poro-steric hindrance of N-aryl groups and electronic effects in newly synthesized neutral salicylaldiminato nickel *** nickel(Ⅱ)catalysts exhibit exceptional thermostability,ranging from 30℃to 130℃,demonstrating enhanced catalytic activities and broadly regulated polyethylene molecular weights(3-341 kg·mol^(-1))and controlled polymer branch density(2-102 brs/1000C).The preferred catalyst Ni3 with concerted steric and electronic effects enables the production of solid-state semi-crystalline polyethylene materials at temperatures below 90℃.Notably,Ni3 exhibits an impressive tolerance of 110℃and can withstand even the challenging polymerization temperature of 130℃,leading to the production of polyethylene wax and ***,functionalized polyethylene is produced.

关键词： Polyolefin Salicylaldiminato ligand Nickel catalyst Oil Wax

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Interface optimization of graphene paper-Cu composite prepared by electrodeposition

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Journal of Iron and Steel Research(International) 2024年第1期31卷 64-73页

作者： Jing Guo Hai-jing Wang Shuang-juan Liu Peng Zhang Jing-yu tang Wei-yang Zhang Han-jie Guo Peng-cheng Wang Cai Meng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of high Energy Physics Chinese Academy of SciencesBeijing100049China advanced technology and materials Co. Ltd.Beijing100083China School of Nuclear science and technology University of Science and Technology of ChinaHefei230027AnhuiChina

A room-temperature electrodeposition method with an organic electrolyte was developed to fabricate a HNO3-pretreated graphene paper Cu(GP'-Cu)*** improve the interfacial bonding of GP'-Cu composite,magnetron sputtering technology was used to create a"sandwich"structural gradient GP'-Cu *** selection of the intermediate transition layer metal was based on two-dimensional *** electron microscopy,X-ray photoelectron spectroscopy,and other analytical methods confirmed that the addition of an intermediate transition metal(Cr,Ni)layer reduced the gap distance and enhanced the interfacial bonding of the GP'and Cu deposited *** GP'-Ni-Cu composite exhibited the largest increase in tensile strength and *** addition,it had the highest thermal diffusivity and elongation at break among the GP'-Cu,GP'-Cr-Cu and GP'-Ni-Cu composites.

关键词： Graphene paper Two-dimensional disregistry Magnetron sputtering Metal composite

Deformation behavior and creep properties of Co-Al-W-based superalloys:A review

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Progress in Natural science:materials International 2021年第5期31卷 641-648页

作者： Yunsong Zhao Yuheng Zhang Yi Zhang Yushi Luo dingzhong tang Haitao Liu Huadong Fu science and technology on advanced high temperature structural materials laboratory Beijing Institute of Aeronautical Materials Institute for advanced materials and technology University of Science and Technology Beijing State key laboratory of Rolling and Automation Northeastern University

Co-Al-W-based superalloys may become a next generation of high-temperature structural materials used in the hot-section of gas turbine because of the discovery of γ’-strengthening mechanism. The current understanding of deformation behavior and creep properties of Co-Al-W-based superalloys is reviewed in this study. It is found that the Co-Al-W-based superalloys have strong anomalous yield stress behavior and better creep properties, making it as an attractive candidate for high-temperature structural material. The relationship between deformation/creep microstructure and the properties of the alloys needs to be further clarified, which can provide deeper theoretical guidance for further composition design, optimization of heat treatment processes, and guidance of alloy service.

关键词： Co-Al-W-based superalloys Deformation behavior Creep properties

Effect of trace boron on microstructural evolution and high temperature creep performance in Re-contianing single crystal superalloys

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Progress in Natural science:materials International 2020年第3期30卷 371-381页

作者： Yunsong Zhao Jian Zhang Fuyang Song Mai Zhang Yushi Luo Hao Zhao dingzhong tang science and technology on advanced high temperature structural materials laboratory Beijing Institute of Aeronautical Materials School of materials science and Engineering Beihang University School of Material science and Engineering University of Science and Technology Beijing China Electronic Product Reliability and Environmental Testing Research Institute

The effect of trace B on the microstructure and creep properties under 1100 °C/130 MPa in three single crystal superalloys with various levels of B(0, 0.01 and 0.02 wt %) additions was investigated. Compared with the boron-free alloy, the creep rupture life decreased slightly for the alloy with 0.01 wt % B, but dropped obviously for the 0.02 wt% B contained alloy. The low B addition had a slight effect on the main element compositions ofγ/γ′ by the high precision atom probe tomography(APT) analysis and no significant change of γ/γ′ misfit was observed. However, the contents of Re, Mo, Cr in γ phase were decreased with the high B addition, resulting in the decrease of γ/γ′ misfit and increase of the spacing of γ/γ′ interfacial dislocation networks. Meanwhile, the residual(γ+γ′) eutectics and borides with a large volume fraction obviously decreased the creep rupture properties in the high B addition alloy. This study is helpful for understanding the boron’s role of strengthening mechanism in high temperature creep of Ni-base single crystal superalloys.

关键词： Superalloys Boron γ/γ′ misfit Borides Creep properties

Effect of the withdrawal rate on the microstructure and thermal durability of a third-generation single crystal superalloy

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Progress in Natural science:materials International 2021年第3期31卷 493-500页

作者： Yunsong Zhao Mai Zhang Luyan Yang Yuanyuan Guo Jian Zhang Hui Lu Yanhui Chen dingzhong tang science and technology on advanced high temperature structural materials laboratory Beijing Institute of Aeronautical Materials Institute of Microstructure and Property of advanced materials Beijing University of Technology

Single crystal Ni-based superalloys are the typical structural materials for high-pressure turbine blades,and their microstructure is critical in determining their mechanical *** withdrawal rate is a key parameter affecting the microstructure during the single crystal growth *** the present work the effect of the withdrawal rate on the microstructure of a third-generation single crystal superalloy containing 6.8 wt% Re has been investigated,and the creep resistance of the alloy *** results showed that increased withdrawal rate refined the dendritic structure,reduced dendritic arm spacing,promoted the growth of secondary tertiary dendrites and decreased solidification segregation with a reduced size of γ’ *** porosity density of the ascast alloy first decreased and then increased with the withdrawal rate,while the minimum porosity densityoccurred when the alloy was under the solidification condition of withdrawal rate of 4.5 mm/*** maximum creep rupture life of 326.4 h of the heat-treated alloys under the test condition of 1100℃/140 MPa also appeared at the alloys under the withdrawal rates of 4.5 mm/*** is believed that the minimum porosity density and reduced size of the γ’ phase may be the main reasons for the enhanced creep rupture life of the alloys with withdrawal rates of 4.5 mm/*** investigation provides theoretical support and a practical basis for the development of third-generation single crystal superalloys.

关键词： Nickel-based superalloy Withdrawal rate Microstructure Thermal durability

Corrosion behavior and failure mechanism of SiC whisker and c-AlPO_(4) particle-modified novel tri-layer Yb_(2)Si_(2)O_(7)/mullite/SiC coating in burner rig tests

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Journal of advanced Ceramics 2022年第12期11卷 1901-1917页

作者： Pengju CHEN Peng XIAO Xian tang Yang LI School of Nuclear science and technology University of South ChinaHengyang 421001China Powder Metallurgy Research Institute Central South UniversityChangsha 410083China national key laboratory of science and technology on high-strength structural materials Central South UniversityChangsha 410083China

The corrosion behavior of environmental barrier coatings(EBCs)directly affects the service life and stability of ceramic matrix composite(CMC)structural parts in the *** silicon carbide(SiC)whisker toughening phase and c-AlPO_(4) bonding phase are firstly used to improve the service life of novel tri-layer Yb_(2)Si_(2)O_(7)/mullite/SiC EBCs in the burner rig *** formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating caused the failure of coating at 1673 *** SiC whiskers in mullite middle coating significantly inhibited the formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating,and efficiently prevented the oxidation of carbon fiber reinforced silicon carbide(C_(f)/SiC)samples for 360-min thermal cycles(24 times)with a weight loss of 6.19×10^(−3) g·cm^(−2).Although c-AlPO_(4) particles further improved the service life of SiC_(w)-mullite(SM)coating,the overflow of PO_(x) gas aggravated the formation and expansion of cracks in the Yb_(2)Si_(2)O_(7) outer coating,and caused the service life of overall Yb_(2)Si_(2)O_(7)/c-AlPO_(4)-SiC_(w)-mullite(ASM)/SiC coating to be slightly lower than that of Yb_(2)Si_(2)O_(7)/SM/SiC *** study guides the design of modified tri-layer EBCs with long service life in high-temperature and high-speed gas environment.

关键词： Yb_(2)Si_(2)O_(7) mullite tri-layer sol-gel burner rig test

Tensile Properties of a Low-cost First Generation Single Crystal Superalloy DD16

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Tensile Properties of a Low-cost First Generation Single Cry...

high efficiency and selectivity catalyst for photocatalytic oxidative coupling of methane

中国材料大会2012

作者： Jianwei Xu Yunsong Zhao dingzhong tang science and technology on advanced high temperature structural materials laboratory State key laboratory for advanced Metals and materials University of Science and Technology Beijing

ISBN: (纸本)9783037856086;3037856084

The tensile properties of a low-cost first generation single crystal superalloy DD16 have been investigated. The results show that values of the tensile strength and yield strength of DD16 alloy were similar at typical temperatures;from room temperature to 760℃, the yield strength of DD16 alloy increases;However, above 760℃, the yield strength of DD16 alloy decreases remarkably, and the maximum of the yield strength was 1145.5MPa at 760℃. From room temperature to 760℃, the fracture mode was cleavage fracture;But above 760℃, the fracture characteristics changed from cleavage to dimple.

关键词： Single crystal superalloy DD16 tensile properties Yield strength

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Chinese Journal of structural Chemistry 2023年第12期42卷 1-2页

作者： Qijun tang Wenguang Tu Yong Zhou Zhigang Zou School of science and Engineering The Chinese University of Hong KongShenzhenGuangdong518172PR China Jiangsu key laboratory for Nano technology National Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresSchool of PhysicsNanjing UniversityNanjing210093PR China

Methane(CH_(4))holds great promise in replacing oil as a building block for chemical commodities[1].However,due to the low-polar nature and high C-H bond energy(439 kJ/mol)of CH_(4),the conversion of CH_(4)by traditional thermocatalysis requires harsh reaction conditions(*** temperature and high pressure)and thus,is energy-consuming[2].To be worse,the production of undesired products like CO_(2)is unavoidable as a result of hydrocarbon combustion reactions[2].

关键词： holds consuming methane

Triggering dynamics of acetylene topochemical polymerization

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Matter and Radiation at Extremes 2023年第5期8卷 82-88页

作者： Xingyu tang Xiao Dong Chunfang Zhang Kuo Li Haiyan Zheng Ho-kwang Mao Center for high Pressure science and technology advanced Research Beijing 100193People’s Republic of China key laboratory of Weak-Light Nonlinear Photonics School of PhysicsNankai UniversityTianjin 300071People’s Republic of China College of Chemistry and materials science Hebei UniversityBaoding 071002People’s Republic of China

Topochemical reactions are a promising method to obtain crystalline polymeric materials with distance-determined regio-or *** has been concluded on an empirical basis that the closest intermolecular C⋅⋅⋅C distance in crystals of alkynes,d(C⋅⋅⋅C)min,should reach a threshold of∼3Åfor bonding to occur at room *** understand this empirical threshold,we study here the polymerization of acetylene in the crystalline state under high pressure by calculating the structural geometry,vibrational modes,and reaction *** find d(C⋅⋅⋅C)min to be the sum of an intrinsic threshold of 2.3Åand a thermal displacement of 0.8Å(at room temperature).Molecules at the empirical threshold move via several phonon modes to reach the intrinsic threshold,at which the intermolecular electronic interaction is sharply enhanced and bonding commences.A distance–vibration-based reaction picture is thus demonstrated,which provides a basis for the prediction and design of topochemical reactions,as well as an enhanced understanding of the bonding process in solids.

关键词： temperature bonding polymerization