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hydrogen absorption and Desorption during Heat Treatment of AISI 4140 Steel

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Journal of Iron and Steel Research International 2014年第10期21卷 951-955页

作者： Ming-da ZHANG Mao-qiu WANG Han DONG National Engineering Research Center of Advanced Steel Technology Central Iron and Steel Research Institute School of Materials Science and Engineering Tsinghua University

hydrogen plays an important role in the formation of quench cracks of structural steels. To clarify hydrogen ab- sorption and desorption during heat treatment of AISI 4140 steel, thermal desorption spectrometry （TDS） analysis was carried out for the specimens in the as-rolled, as quenched, and quenched and tempered conditions. Results show that hydrogen content increased from 0. 127 ×10 6 in the as-rolled specimen to 0. 316 × 10-6 in the as-oil-quenched specimen. After tempering at 200 ℃, the hydrogen content in the oil-quenched specimen decreased to 0. 155 × 10-6 , and the peak temperature of hydrogen desorption increased from 200 to 360 ℃. From the dependence of hydrogen content in the as-quenched specimens on austenitizing time, it can be deduced that hydrogen absorption occurs during austenitizing. The simulation of hydrogen absorption contributes to a better understanding on the distribution of hy- drogen during the heat treatment in structural steels.

关键词： steel hydrogen absorption heat treatment thermal desorption spectrometry

hydrogen absorption OF FeTi+x wt-% La ALLOYS WITH ALTERNATE LAYER STRUCTURE

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Acta Metallurgica Sinica(English Letters) 1992年第5期5卷 354-357页

作者： QIAN Jiuxin ZHANG Yawen CHEN Xudong Peking University,Beijing,China Peking Univ Beijing China

Superior hydrogen absorbability of the alloys fo FeTi-La with alternate layer structure was found *** would be available at 30℃ under 6 MPaH_2 without any prior treatment.

关键词： FeTi La hydrogen absorption

Structure of Liquid Aluminum and hydrogen absorption

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Journal of Wuhan University of Technology(Materials Science) 2011年第1期26卷 93-97页

作者：柳洋孙宝德 State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University

The hydrogen content in aluminum melts at different temperature was detected. The structure in aluminum melts was investigated by molecular dynamics simulation. The first peak position of pair correlation function, atomic coordination number and viscosity of aluminum melts were calculated and they changed abnormally in the same temperature range. The mechanism of hydrogen absorption has been discussed. From molecular dynamics calculations, the interdependence between melt structural properties and hydrogen absorption were obtained.

关键词： hydrogen absorption aluminum melts liquid structure viscosity molecular dynamics simulation

Isothermal hydrogen absorption process of Pd-capped Mg films traced by ion beam techniques and optical methods

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Journal of Magnesium and Alloys 2024年第9期12卷 3675-3684页

作者： D.Abejón P.Prieto J.K.Kim A.Redondo-Cubero M.L.Crespillo F.Leardini I.J.Ferrer G.García J.R.Ares Departamento de Fisica de Materiales Universidad Autónoma de MadridMadrid28049Spain Centro de Micro-Análisis de Materiales(CMAM) Universidad Autónoma de MadridMadrid28049Spain Advanced Analysis Center KIST5 Hwarang-ro 14-gilSeoul 02792Republic of Korea Departamento de Física Aplicada Universidad Autónoma de MadridMadrid28049Spain Instituto Nicolás Cabrera Universidad Autónoma de MadridMadrid28049Spain

Pd-capped nanocrystalline Mg films were prepared by electron beam evaporation and hydrogenated under isothermal conditions to inves-tigate the hydrogen absorption process via ion beam techniques and in situ optical *** were characterized by different techniques such as X-ray diffraction(XRD)and scanning electron microscopy(SEM).Rutherford backscattering spectrometry(RBS)and elastic recoil detection analysis(ERDA)provided a detailed compositional depth profile of the films during ***-solid reaction kinetics theory applied to ERDA data revealed a H absorption mechanism controlled by H *** rate-limiting step was also confirmed by XRD *** diffusion coefficient(D)was also determined via RBS and ERDA,with a value of(1.1±0.1)·10^(−13)cm^(2)/s at 140℃.Results confirm the validity of IBA to monitor the hydrogenation process and to extract the control mechanism of the *** H kinetic information given by optical methods is strongly influenced by the optical absorption of the magnesium layer,revealing that thinner films are needed to extract further and reliable information from that technique.

关键词： Magnesium hydride hydrogen absorption Ion beam techniques Optical tracing absorption mechanism

hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： Kai Yin Xiaopeng Liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm hydrogen absorption Nitrogen absorption Rare earths

Impact of severe plastic deformation on kinetics and thermodynamics of hydrogen storage in magnesium and its alloys

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Journal of Materials Science & Technology 2023年第15期146卷 221-239页

作者： Kaveh Edalati Etsuo Akiba Walter J.Botta Yuri Estrin Ricardo Floriano Daniel Fruchart Thierry Grosdidier Zenji Horita Jacques Huot Hai-Wen Li Huai-Jun Lin Ádám Révész Michael J.Zehetbauer WPI International Institute for Carbon-Neutral Energy Research(WPI-I2CNER)Kyushu UniversityFukuokaJapan International Research Center for hydrogen Energy Kyushu UniversityFukuokaJapan Departamento de Engenharia de Materiais Universidade Federal de São CarlosSao Carlos-SPBrazil Department of Materials Science and Engineering Monash UniversityClaytonVIC 3800Australia Department of Mechanical Engineering the University of Western AustraliaCrawleyWA 6009Australia School of Applied Sciences University of Campinas(UNICAMP)LimeiraSão PauloBrazil Institut Néel CNRS&UGA38042 GrenobleFrance JOMI-LEMAN SA 74890 FessyFrance Universitéde Lorraine Laboratory of Excellence on Design of Alloy Metals for low-mass Structures(DAMAS)MetzF-57070France Universitéde Lorraine Laboratoire d’Etude des Microstructures et de Mécanique des Matériaux(LEM3 UMR 7239)MetzF-57070France Graduate School of Engineering Kyushu Institute of TechnologyKitakyushuJapan Magnesium Research Center Kumamoto UniversityKumamotoJapan Synchrotron Light Application Center Saga UniversitySagaJapan hydrogen Research Institute Universitédu QuébecàTrois-Rivières3351 des ForgesTrois-RivièresQC G9A 5H7Canada Hefei General Machinery Research Institute Hefei 230031China Institute of Advanced Wear&Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou 510632China Department of Materials Physics Eötvös UniversityBudapestH-1518P.O.B.32BudapestHungary Faculty of Physics University of ViennaBoltzmanngasse 5A-1090 WienAustria

Magnesium and its alloys are the most investigated materials for solid-state hydrogen storage in the form of metal hydrides,but there are still unresolved problems with the kinetics and thermodynamics of hydrogenation and dehydrogenation of this group of *** plastic deformation(SPD)methods,such as equal-channel angular pressing(ECAP),high-pressure torsion(HPT),intensive rolling,and fast forging,have been widely used to enhance the activation,air resistance,and hydrogenation/dehydrogenation kinetics of Mg-based hydrogen storage materials by introducing ultrafine/nanoscale grains and crystal lattice *** severely deformed materials,particularly in the presence of alloying additives or second-phase nanoparticles,can show not only fast hydrogen absorption/desorption kinetics but also good cycling *** was shown that some materials that are apparently inert to hydrogen can absorb hydrogen after SPD ***,the SPD methods were effectively used for hydrogen binding-energy engineering and synthesizing new magnesium alloys with low thermodynamic stability for reversible low/room-temperature hydrogen storage,such as nanoglasses,high-entropy alloys,and metastable phases including the high-pressureγ-MgH2 *** work reviews recent advances in the development of Mg-based hydrogen storage materials by SPD processing and discusses their potential in future applications.

关键词： Severe plastic deformation(SPD) Nanostructured materials Ultrafine-grained(UFG)materials Magnesium hydride(MgH_(2)) Magnesium-based alloys hydrogen absorption hydrogenation kinetics hydrogen storage thermodynamics

Magnetic entropy change and magnetic properties of LaFe_(11.5)Si_(1.5) after controlling the Curie temperature by partial substitution of Mn and hydrogenation

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Chinese Physics B 2016年第2期25卷 459-462页

作者：傅斌韩洁 School of Materials Science and Engineering Tianjin University of Technology Tianjin 300384 China College of Science Tianjin University of Technology Tianjin 300384 China

Magnetic properties and magnetic entropy changes of La（Fe_（1-x）Mn_x）_（11.5）Si_（1.5）H_y compounds are investigated. Their Curie temperatures are adjusted to room temperature by partial Mn substitution for Fe and hydrogen absorption in 1-atm（1 atm = 1.01325×10~5Pa） hydrogen gas. Under a field change from 0 T to 2 T, the maximum magnetic entropy change for La（Fe_（0.99）Mn_（0.01））_（11.5）Si_（1.5）H_（1.61）is-11.5 J/kg. The suitable Curie temperature and large value of ？S_m make it an attractive potential candidate for the room temperature magnetic refrigeration application.

关键词： magnetic refrigeration Curie temperature (Tc) hydrogen absorption magnetocaloric effect(MCE)

Boundary Element Method (BEM) Analysis for Galvanic Corrosion of Hot Dip Galvanized Steel Immersed in Seawater

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Journal of Materials Science & Technology 2009年第2期25卷 194-198页

作者： Xiao Tang Yuzhi Zhang Meng Liu Yan Li Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A numerical analysis of galvanic corrosion of hot-dip galvanized steel immersed in seawater was presented. The analysis was based on the boundary element methods （BEMs） coupled with Newton-Raphson iterative technique to treat the nonlinear boundary conditions, which were determined by the experimental polarization curves. Results showed that galvanic current density concentrates on the boundary of steel substrate and zinc coating, and the sacrificial protection of zinc coating to steel substrate results in overprotection of steel cathode. Not only oxygen reduction but also hydrogen reduction could occur as cathode reactions, which probably led up to the adsorption and absorption of hydrogen atoms. Flat galvanized steel tensile sample shows a brittle behavior similar to hydrogen embrittlement according to the SSRT （show strain rate test） in seawater.

关键词： Galvanic corrosion BEM hydrogen absorption Potential distribution Current density distribution

Kinetics of Liquid-Phase hydrogenation of Benzene in a Metai Hydride Slurry System Formed by MlNi_5 and Benzene

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Chinese Journal of Chemical Engineering 2003年第5期11卷 571-576页

作者：代世耀徐国华安越陈长聘陈立新王启东 Department of Chemical Engineering Department of Materials Science Zhejiang University Hangzhou 310027China

The kinetics of liquid-phase hydrogenation of benzene in misch metai nickel-five (MINi5) and benzene slurry system was studied by investigating the influences of the reaction temperature, pressure, alloy concentration and stirring speed on the mass transfer-reaction processes inside the slurry. The results show that the whole process is controlled by the reaction at the surface of the catalyst. The mass transfer resistance at gas-liquid interface and that from the bulk liquid phase to the surface of the catalyst particles are negligible. The apparent reaction rate is zero order for benzene concentration and first order for hydrogen concentration in the liquid phase. The kinetic modei obtained fits the experimental data very well. The apparent activation energy of the hydrogen absorption reaction of MINi5-C6H6 slurry system is 42.16kJ·mol-1.

关键词： hydrogen storage slurry hydrogen storage alloy aromatics hydrogen absorption