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Crystallization kinetics of (Ni_(0.75)Fe_(0.25)_(78-x)Nb_xSi_(10)B_(12)(x=0,5)amorphous alloys

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Rare Metals 2006年第4期25卷 342-348页

作者： CHEN Xueding WEI Hengdou WANG Xiaojun State Key Laboratory of Advanced New Non-ferrous materials l.anzhou University of Technology l.anzhou 730050 China

amorphous ribbons of （Ni0.75Fe0.25）78-xNbxSi10B12 （x = 0, 5） were prepared by a single roller melt-spinning technique in air atmosphere. The crystallization kinetics of the alloys were investigated by means of continuous heating, and the activation energies of the alloys were calculated using Kissinger plot method and Ozawa plot method on the basis of differential thermal analysis data. The crystallization products were analyzed by X-ray diffraction. After the （Ni0.75Fe0.25）78Si10B12 amorphous alloy was annealed at the temperatures 715 and 745 K, a single phase of γ-（Fe, Ni） solid solution with grain sizes of about 10.3 and 18.5 nm, respectively, precipitates in the amorphous matrix. The crystallized phases are γ-（Fe, Ni） solid solution, Fe2Si, Ni2Si, and Fe3B after annealing at 765 K. The （Ni0.75Fe0.25）73NbsSi10 B12 amorphous alloy was annealed at 720, 750, and 800 K; and the crystallization phases, γ（Fe, Ni） solid solution, （Fe, Ni）23B6. Ni31Si12 and Nb2NiB0.16 form simultaneously.

关键词： amorphous materials thermal analysis crystallization kinetics activation energy

amorphous MoS_(3) enriched with sulfur vacancies for efficient electrocatalytic nitrogen reduction

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Journal of Energy Chemistry 2021年第2期30卷 132-138,I0005页

作者： Ke Chu Haifeng Nan Qingqing Li Yali Guo YeTian Wuming Liu School of materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070GansuChina Department of Physics College of ScienceHebei North UniversityZhangjiakou 075000HebeiChina Institute of Physics Chinese Academy of SciencesBeijing 100190China

Developing low-priced,yet effective and robust catalysts for the nitrogen reduction reaction(NRR) is of vital importance for scalable and renewable electrochemical NH3 ***,we provide the first demonstration of MoS_3 as an efficient and durable NRR catalyst in neutral *** prepared amorphous MoS_3 naturally possessed enriched S vacancies and delivered an NH3 yield of 51.7 μg h^(-1) mg^(-1)and a Faradaic efficiency of 12.8% at-0.3 V(RHE) in 0.5 M LiClO_4,considerably exceeding those of MoS_2 and most reported NRR *** functional theory calculations unraveled that S vacancies involved in MoS_3 played a crucial role in activating the NRR via a consecutive mechanism with a low energetics barrier and simultaneously suppressing the hydrogen evolution reaction.

关键词： Electrocatalytic N_2 reduction amorphous materials Vacancy N_(2)activation

Accurate prediction method for the microstructure of amorphous alloys without non-metallic elements

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Chinese Physics B 2021年第11期30卷 440-444页

作者： Wei Zhao Jia-Lin Cheng Gong Li Xin Wang School of materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China State Key Laboratory of Metastable materials Science and Technology Yanshan UniversityQinhuangdao 066004China Jiangsu Key Laboratory of Advanced Structural materials and Application Technology Nanjing 211167China School of materials Science and Engineering Harbin University of Science and TechnologyHarbin 150080China

A new structural parameter of amorphous alloys called atomic bond proportion was proposed, and a topological algorithm for the structural parameter was proven feasible in the previous work. In the present study, a correction factor, λ,is introduced to optimize the algorithm and dramatically improve the calculation accuracy of the atomic bond *** correction factor represents the ability of heterogeneous atoms to combine with one another to form the metallic bonds and it is associated with the uniformity of the master alloy, mixing enthalpy, cooling rate during preparation, and annealing time. The correction factor provides a novel pathway for researching the structures of the amorphous alloys.

关键词： atomic bond proportion correction factor amorphous materials microstructure

Emergent Physics on the Route from Crystals to amorphous Solids

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Chinese Journal of Chemistry 2022年第9期40卷 1091-1098页

作者： Zhehua Jiang Ning Xu Department of Physics and CAS Key Laboratory of Microscale Magnetic Resonance University of Science and Technology of ChinaHefeiAnhui 230026China

By introducing and graduly increasing the magnitude of disorder into both crystallineparticle packings and crystalline networks,we realize the evolution from crystals to amorphous *** evolution of structures and mechanical properties during this process is expected to help,us understand the physical origin of the peculiar properties of amorphous solids,***,so as to buildupthebridgebetween wll-established physics of crystals and that of amorphous *** our surprise,this attempt also reveals some extraordinary phenomena,including the hidden order-disorder transition from crystals to disordered crystals and the emergence of mechanical metamaterials with negative Poisson's ratios.

关键词： amorphous materials Glasses Phase transitions Disordered crystals Auxetic materials

CRYSTALLIZATION KINETICS OF Al83Y10Ni7(at％) amorphous ALLOYS

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Chinese Journal of Aeronautics 1995年第4期8卷 263-270页

作者： Mengyan Yang Gencang(Department 4, Northwestern Polytechnical University, Xi’an, China, 710072)

Crystallization kinetics of Al83Y10Ni7(at%) amorphous alloys prepared bymelt spinning was studied by differential scanning calorimetry (DSC). Three or fourstages of transforniation from amorphous to equilibrium state can be distinguished atheating rate 1 ￣ 40K / min. Apparent activation energies are calculated according to themethods of Kissinger, Ozawa and Arrhernius equation. An amoaphous phase with highstructural and heat stability was obtained in the vicinity of Al83Y10,Ni7. The isotheimalcrystallization kinetics of the first peak, in the range of 0. 15￣ 0.85, was found to be inagreement with John-Mell-Avrami equation with n = 2.5. Nucleation and growth dur-ing isothennal crystallization of the first stage for Al83Y10Ni7 amorpohous were ap-proached by introducing the concept of local Avrami exponent and local activation en-ergy.

关键词： amorphous materials kinetics characteristics activation energy

Curie Temperature of amorphous Fe-Si-B and Fe-W-Si-B Alloys

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Rare Metals 1998年第2期17卷 2-8页

作者：王玲玲赵立华胡望宇吴力军张邦维湖南大学物理系湖南长沙湖南大学材料研究与测试中心湖南长沙中科院国际材料物理中心辽宁沈阳

オhe effects of composition, annealing temperature and time, annealing heating rate on the Curie temperature of amorphous FeSiB and FeWSiB alloys were studied. The results indicate that the Curie temperature of these alloys increases with the increase of the metalloid content when it is amorphous FeSiB and FeWSiB alloys with the low metalloid content, the Curie temperature increases with the annealing temperature and the annealing time. However, for the amorphous FeWSiB alloys with the high metalloid content, the Curie temperature increases at low annealing temperature and with short annealing time, and decreases at high annealing temperature and with long annealing time. The heating rate in measuring Curie temperature also influences the Curie temperature of the alloys. The Curie temperature is higher at lower heating rates.

关键词： Curie temperature FeSiB and FeWSiB alloys amorphous materials

Iridium single-atom catalyst for highly efficient NO electroreduction to NH_(3)

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Nano Research 2023年第7期16卷 8737-8742页

作者： Kai Chen Guohui Wang Yali Guo Dongwei Ma Ke Chu School of materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Key Laboratory for Special Functional materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China

Atomically dispersed Ir confined in amorphous MoO_(3)(Ir1/a-MoO_(3))was designed as a high-efficiency catalyst for electrochemical reduction reaction of NO to NH_(3)(NORR).Atomic precise characterizations reveal that isolated Ir atoms are immobilized in Ovacancies of amorphous MoO_(3) to form Ir_(1)-O_(5) *** computations demonstrate that single-site Ir1-O5 can not only powerfully activate and hydrogenate NO with a near-zero energy barrier,but also exhibit a higher affinity to NO over H adatoms to suppress the competing hydrogen evolution and promote both NORR activity and ***,Ir_(1)/a-MoO_(3) shows the maximum NH_(3)yield rate of 438.8μmol·h^(-1)·cm^(-2) and NH_(3)-Faradaic efficiency of 93.2%,representing one of the most efficient NORR catalysts to date.

关键词： electrochemical reduction of NO to NH_(3) single-atom catalysts amorphous materials theoretical calculations

Luminescence characteristics of Dy^(3+) doped Gd_2O_3-CaO-SiO_2-B_2O_3 scintillating glasses

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Journal of Rare Earths 2016年第6期34卷 583-589页

作者： J.Kaewkhao N.Wantana S.Kaewjaeng S.Kothan H.J.Kim Center of Excellence in Glass Technology and materials Science (CEGM) Nakhon Pathom Rajabhat University Department of Radiologic Technology Faculty of Associated Medical Sciences Chiang Mai University Department of Physics Kyungpook National University

Glasses were prepared from the compositions of 25Gd_2O_3-10 CaO-10 SiO_2-（55–x）B_2O_3-xDy_2O_3（where x is 0.0 mol.%–1.0 mol.%） by the conventional melt-quenching technique at 1400 oC. The results demonstrated the increase in the glass density with respect to the increase in the doping concentrations of Dy_2O_3. Nine absorption bands were observed. The emission spectra of the developed glass showed two strong peaks at 577 nm（~4F_（9/2）→~6H_（13/2）） and 482 nm（~4F_（9/2）→~6H_（15/2））. The highest emission intensity was observed from the developed glass prepared at 0.4 mol.% of Dy_2O_3, as the efficient energy transfer took place from Gd^（3＋） to Dy^（3＋）. From the X-ray induced optical luminescence, the emission spectra were identical to those from PL measurements, but with the highest intensity observed from the glass quenched at 0.45 mol.% of Dy_2O_3. Finally, the integral scintillation efficiency of the developed glass was determined at 27% of that of the commercially available BGO crystal.

关键词： amorphous materials glasses oxides optical properties luminescence rare earths

Effects of rare-earth elements on the glass-forming ability and mechanical properties of Cu_(46)Zr_(47-x)Al_7M_x(M = Ce,Pr,Tb,and Gd) bulk metallic glasses

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Rare Metals 2010年第5期29卷 444-450页

作者： XIE Zhiwei ZHANG Yongzhang YANG Yuanzheng CHEN Xianzhao TAO Pingjun Faculty of Material and Energy Guangdong University of Technology Guangzhou 510006 China

Cu46Zr47-xA17Mx （M = Ce, Pr, Tb, and Gd） bulk metallic glassy （BMG） alloys were prepared by copper-mold vacuum suction casting. The effects of rare-earth elements on the glass-forming ability （GFA）, thermal stability, and mechanical properties of Cu46Zr47-xA17Mx were investigated. The GFA of Cu46Zr47-xA17Mx （M = Ce, Pr） alloys is dependent on the content of Ce and Pr, and the optimal content is 4 at.%. Cu46Zr47-xA17Thx（X = 2, 4, and 5） amorphous alloys with a diameter of 5 mm can be prepared. The GFA of Cu46Zr47-xA17Gdx（x = 2, 4, and 5） increases with increasing Gd. Tx and Tp of all decrease. Tg is dependent on the rare-earth element and its content. ATx for most of these alloys decreases except the Cu46Zra2Al7Gd5 alloy. The activation energies △Eg, △Ex, and △Ep for the Cu46Zr42A17Gd5 BMG alloy with Kissinger equations are 340.7, 211.3, and 211.3 kJ/mol, respectively. These values with Ozawa equations are 334.8, 210.3, and 210.3 kJ/mol, respec- tively. The Cu46Zr45Al7Tb2 alloy presents the highest microhardness, Hv 590, while the Cu46Zr43A17Pr4 alloy presents the least, Hv 479. The compressive strength （at.f.） of the Cu46Zra3A17Gd4 BMG alloy is higher than that of the Cu46Zr43Al7Tb4 BMG alloy.

关键词： amorphous materials metallic glass rare-earth elements suction casting glass-forming ability mechanical property