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Rare metals 2017年第1期36卷 55-60页

作者： Ming Wu Yang Chen Jia-Qing Peng Guo-Qing Yan Yu-Pu Sun Jian-Dong Zhang Shun-Li Zhang Li-Jun Wang Division of Rare metals Metallurgy and Materials General Research Institute for Nonferrous Metals Beijing 100088 China

The hydrogen permeation resistance of Si–Zr(SZ) and Si–Al(sa) composite sol oxide coating on zirconium hydride blocks(Zr H) was studied. SZ and sa composite sol were prepared by sol–gel method. SZ and sa composite oxide coatings were prepared on the surface of Zr H(in situ oxidized or not) in turns by dip-coating and heat treatment. Hydrogen permeation of Zr Hwith and without composite oxide coating was *** desorption experiments in thermal vacuum show that hydrogen permeation resistance of sa composite oxide coating is better than that of SZ, to a certain extent,which could decrease hydrogen thermal loss. Experimental results in the working condition show that the sa composite oxide coating can not only prevent hydrogen permeation, but also retard contact and reaction between COand Zr Hmatrix, which could mitigate excessive oxidation of in situ oxide film. Differential scanning calorimetry and thermogravimetry(DSC–TG) analysis was performed to investigate the decomposition behavior of sa and SZ liquid sol in heat treatment process. X-ray diffraction(XRD) and scanning electron microscopy(SEM) analysis were employed to characterize the phase composition,surface and cross-section morphology of the coatings.

关键词： Zirconium hydride Hydrogen permeation resistance Composite oxide coating Si–Zr Si–Al Sol–gel

深冷和去应力处理对AISID2工具钢回火碳化物析出的影响

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热处理 2015年第4期30卷 49-53页

作者： P.F.da Silva Farina A.Bellegard Farina C.Antonio Barbosa H.Goldenstein 顾剑锋 Escola Polite'cnica da Universidade de So Paulo villares metals sa 本刊编委会上海交通大学

研究了深冷和去应力处理对D2冷作工具钢回火碳化物析出的影响。深冷处理温度为-196℃,保温时间分别为2 h、24 h和30 h;去应力处理工艺为130℃×90 min。所有试样都与经常规工艺热处理的试样作了对比。采用金相分析、X-射线衍射(XRD)和... 详细信息

研究了深冷和去应力处理对D2冷作工具钢回火碳化物析出的影响。深冷处理温度为-196℃,保温时间分别为2 h、24 h和30 h;去应力处理工艺为130℃×90 min。所有试样都与经常规工艺热处理的试样作了对比。采用金相分析、X-射线衍射(XRD)和温差电势法研究了经深冷和去应力处理的试样。除了OM外,还选用了扫描电镜(SEM)和场发射扫描电镜(SEM-FEG)进行微观组织表征。结果表明,经深冷或去应力处理的试样中二次碳化物(微米级)析出未发生变化。经深冷处理但未经去应力处理的试样基体中,回火二次碳化物(纳米级)比较细小而弥散。回火二次碳化物的细化可能是回火过程中碳化物的原位析出所致。

关键词：去应力深冷处理工具钢

Geological and geochemical characteristics and metallogenic model of the Wenquan molybdenum deposit

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Chinese Journal Of Geochemistry 2011年第3期30卷 391-397页

作者： WU Zicheng LIU Jishun HAN Haitao DONG Xin OUYANG Yufei School of Geosciences and Environmental Engineering Central South University Changsha 410083 China Gansu Institute of Geology for Nonferrous metals Lanzhou 730000 China Tianshui General Party of Gansu Nonferrous metals Geological Exploration Bureau Tianshui 741025 China

The Wenquan molybdenum deposit is a kind of large-sized porphyry molybdenum deposit found in re-cent *** this paper,on the basis of deposit geology,geochemistry and isotope geochronology data,the metal-logenic model of this deposit was *** Wenquan granitic batholith belongs to the K-rich(alkali-rich) calc-alkaline rock series,which is the mineralization parent *** rock massif shows the characteristics of both crust-remelting granite and mantle-source *** the same time,the data of REE contents,hydrogen and oxygen isotopes and inclusion temperatures showed that the metallogenic hydrothermal solution is a mixed mesothermal solution of magmato-hydrothermal fluid and meteoric *** was dated at 214±7.1 Ma,basically identical with the parent rock's age(207-226 Ma).This reflects that molybdenum mineralization has a close relation to tectonic magmatism evoked by orogenic processes,and molybdenum mineralization occurred mainly at the petrogenesis stage at the late stage of magma *** with meteoric water led to a decrease in the sa-linity of magmato-hydrothermal solution and changes in other physical and chemical *** the tectonic process,ore-bearing hydrothermal solution ascended along favorable fault structure *** physicochemical changes,it filled in the surrounding rock joints on both sides of faults,forming ore deposits.

关键词：地质地球化学钼矿床成矿模式温泉特征和构造岩浆活动物理化学变化同位素年代学

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淬火工艺对高速钢力学性能的影响

热处理 2013年第4期28卷 59-64页

作者： R.A.Mesquita C.A.Barbosa C.S.Goncalves A.L.Slaviero 顾剑锋 Universidade Nove de Julho Sao PauloBrazil villares metals Sumare'Brazil 上海交通大学

高速钢工具的耐磨性等性能主要决定于它的硬度和韧性。主要研究了淬火温度和冷速对高速钢韧性的影响。分别在实验室和工业热处理炉中模拟了几种工艺规范，并用静弯曲试验来评估韧性。在同样回火条件下，淬火温度越高，获得的硬度也越高... 详细信息

高速钢工具的耐磨性等性能主要决定于它的硬度和韧性。主要研究了淬火温度和冷速对高速钢韧性的影响。分别在实验室和工业热处理炉中模拟了几种工艺规范，并用静弯曲试验来评估韧性。在同样回火条件下，淬火温度越高，获得的硬度也越高。研究结果显示了低于1200℃淬火的高速钢硬度与韧性之间关系。淬火温度高于1200℃时，韧性显著降低而硬度无明显升高。同时论述了热处理后硬度较低的M2高速钢的力学性能，而某些冷作工具的应用中需要较低热处理硬度。在这种情况下，从较低温度淬火并回火到最高硬度的效果最佳。最后，关于真空炉氮气淬火冷却工艺的研究结果表明，低的淬火压力可以减慢冷速和降低材料韧性，但淬火压力为（6～9）×105 Pa时导致的差别很小。

关键词： M2 高速钢淬火温度冷速韧性弯曲试验

Laser ablation(in situ)Lu-Hf dating of magmatic fluorite and hydrothermal fluorite-bearing veins

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Geoscience Frontiers 2023年第6期14卷 142-154页

作者： Stijn Glorie Jacob Mulder Martin Hand Adrian Fabris Alexander Simpson sarah Gilbert Department of Earth Sciences University of AdelaideSA 5005Australia Geological Survey of South Australia Department for Energy and MiningAdelaideSA 5005Australia Adelaide Microscopy University of AdelaideSA 5005Australia

Fluorite(CaF_(2))is a common hydrothermal mineral,which precipitates from fluorine-rich fluids with an exceptional capacity to transport metals and Rare Earth Elements(REEs).Hence,the ability to date fluorite has important implications for understanding the timing of metal transport in hydrothermal *** we present,for the first time,fluorite Lu-Hf dates from fluorite-carbonate veins from the Olympic Cu-Au Province in South *** fluorite dates were obtained in situ using the recently developed LA-ICP-MS/MS Lu-Hf dating method.A fluorite-calcite age of 1588±19 Ma was obtained for the Torrens Dam prospect,consistent with the timing of the formation of the nearby Olympic Dam iron-oxide copper gold Breccia *** in the overlying Neoproterozoic successions were dated at 502±14 Ma,indicating a temporal link between Cu-sulphide remobilisation and the Delamerian ***,we present a multi-session reproducible date for magmatic fluorite from a monzogranite in the Pilbara Craton(Lu-Hf age of 2866±19 Ma).This age is consistent with a garnet Lu-Hf age from the same sample(2850±12 Ma)and holds potential to be developed into a secondary reference material for future fluorite Lu-Hf dating.

关键词： Reaction-cell ICP-MS In-situ geochronology Fluorite-calcite veins Iron oxide copper-gold Critical mineral exploration Rare Earth Elements

Effect of processing parameters on the microstructure and mechanical properties of TiAl/Ti_(2)AlNb laminated composites

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Journal of Materials Science & Technology 2022年第14期109卷 228-244页

作者： Donghai Li Binbin Wang Liangshun Luo Xuewen Li Yanjin Xu BinQiang Li Diween Hawezy Liang Wang Yanqing Su Jingjie Guo Hengzhi Fu National Key Laboratory for Precision Hot Processing of metals School of Materials Science&EngineeringHarbin Institute of TechnologyHarbin 150001China Key Laboratory for Lightweight Materials Nanjing Tech UniversityNanjing 211816China AVIC Manufacturing Technology Institute Beijing 100024China Materials Research Centre College of EngineeringSwansea UniversityBay CampusSwansea SA18ENUK

In order to improve the intrinsic brittleness of TiAl alloys,Ti_(2)AlNb alloys with outstanding ductility and toughness at room temperature,and good high-temperature performance are competitive candidates in constructing the TiAl-based laminated *** this work,TiAl/Ti_(2)AlNb laminated composites are successfully synthesized by vacuum hot pressing combined with the foil-foil(sheet)*** the pressure of 65 MPa,different holding time and temperature of hot pressing are tried and the optimized fabrication parameter is acquired as 1050℃/120 min/65 *** with the changes of processing parameters,the defect,microstructure,interface,phase transformation and the corresponding mechanical properties are detailly *** results show that the TiAl/Ti_(2)AlNb laminated composite fabricated at 1050℃ for 2 h achieves a good metallurgical interface *** corresponding interface microstructure is composed of region I and region *** region I consists of O,α_(2)and B2/βphase,and region II is made up ofα***,the tensile tests indicate that the composite synthesized at 1050℃ for 2 h possesses a maximum strength of 812 MPa and a total elongation of 1.31%at room temperature,and a strength of 539.71 MPa and the highest total elongation of 10.34%at 750℃.The well synergistic deformation ability between the interface and the two base alloys endows the composite an excellent tensile ***,the composite processed at 1050℃ for 2 h behaves the best fracture toughness in both arrester orientation and divider orientation with the value of 32.6 MPa.m^(1/2)and 30.1 MPa.m^(1/2),*** Ti_(2)AlNb alloy in the laminated structure effectively release the stress around the crack tip and plays a role in ***,crack deflection,crack bridging,crack blunting and fragmentation also make contributions to enhance the fracture toughness of the laminated composites.

关键词： TiAl/Ti_(2)AlNb laminated composite Hot pressing Processing parameters Microstructure Mechanical properties Fracture

Microencapsulation of stearic acid with polymethylmethacrylate using iron(Ⅲ) chloride as photo-initiator for thermal energy storage

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1524-1532页

作者： Ting Zhang Minmin Chen Yu Zhang Yi Wang College of Petrochemical Technology Lanzhou University ofTechnology Lanzhou 730050 China State Key Laboratory of Advanced Processing and Recycling of Nonferrous metals Lanzhou University ofTechnology Lanzhou 730050 China

Aiming to identify the validity of fabricating microencapsulated phase change material(PCM) with polymethylmethacrylate(PMMA) by ultraviolet curing emulsion polymerization method using iron(III) chloride as photoinitiator,sa/PMMA microcapsules were prepared and various techniques were employed to determine the ignition mechanism,structural characteristics and thermal properties of the *** results shown that the microcapsules containing sa with maximum percentage of 52.20 wt% formed by radical mechanism and only physical interactions existed in the components both in the prepared process and subsequent *** phase change temperatures and latent heats of the microencapsulated sa were measured as 55.3 °C and 102.1 J·g^(-1) for melting,and 48.8 °C and 102.8 J·g^(-1) for freezing,*** gravimetric analysis revealed that sa/PMMA has good thermal durability in working temperature *** results of accelerated thermal cycling test are all shown that the sa/PMMA have excellent thermal reliability and chemical stability although they were subjected 1000 melting/freezing *** summary,the comparable thermal storage ability and good thermal reliability facilitated sa/PMMA to be considered as a viable candidate for thermal energy *** successful fabrication of sa/PMMA capsules indicates that ferric chloride is a prominent candidate for synthesizing PMMA containing PCM composite.

关键词： Thermal energy storage Phase change material Microencapsulation Thermodynamic properties Synthesis Photochemistry

Advances in additively manufactured titanium alloys by powder bed fusion and directed energy deposition:Microstructure,defects,and mechanical behavior

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Journal of Materials Science & Technology 2024年第16期183卷 32-62页

作者： H.Y.Ma J.C.Wang P.Qin Y.J.Liu L.Y.Chen L.Q.Wang L.C.Zhang Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA 6027SA School of Engineering M050The University of Western Australia35 Stirling HighwayCrawleyPerthWA 6009SA Institute of metals College of Material Science and EngineeringChangsha University of Science&TechnologyChangsha 410004China School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China State Key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Ti and its alloys have been broadly adopted across various industries owing to their outstanding proper-ties,such as high strength-to-weight ratio,excellent fatigue performance,exceptional corrosion resistance and so *** manufacturing(AM)is a complement to,rather than a replacement for,traditional manufacturing *** enhances flexibility in fabricating complex components and resolves machin-ing challenges,resulting in reduced lead times for custom ***,owing to distinctions among various AM technologies,Ti alloys fabricated by different AM methods usually present differences in mi-crostructure and defects,which can significantly influence the mechanical performance of built ***,having an in-depth knowledge of the scientific aspects of fabrication and material properties is crucial to achieving high-performance Ti alloys through different AM *** article reviews the mechanical properties of Ti alloys fabricated by two mainstream powder-type AM techniques:powder bed fusion(PBF)and directed energy deposition(DED).The review examines several key aspects,en-compassing phase formation,grain size and morphology,and defects,and provides an in-depth analysis of their influence on the mechanical behaviors of Ti *** review can aid researchers and engi-neers in selecting appropriate PBF or DED methods and optimizing their process parameters to fabricate high-performance Ti alloys for a wide range of industrial applications.

关键词： Powder bed fusion Directed energy deposition Titanium alloys Phase transformation Defects Mechanical property

Effect of phosphatation and calcination on the environmental behaviour of sediments

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International Journal of Sediment Research 2019年第5期34卷 486-495页

作者： Moussa Dia Rachid Zentar Nor-edine Abriak Ange Nzihou Guy Depelsenaire Alain Germeau Department of Civil & Environmental Engineering Toulouse University Mines Albi CNRS RAPSODEE Center Campus Jarlard SOLVAY sa DCRT 4. PRAYON sa

Dredging operations produce considerable quantities of materials, to be managed and this opens an opportunity for valorization in civil engineering. However, the contamination of the dredged sediment has become a major problem to solve. The major contaminants are heavy metals and organic compounds This study focuses on the use of phosphoric acid(H3 PO4) to stabilize heavy metals from sediments an destroy organic matter by calcination at 650 °C with a goal of using sediments in roadworks. Severa studies have been conducted in this field. The stabilized materials obtained have been used in civ engineering. The main purpose of this work is to discuss the environmental behavior of marine sedimen treated by phosphatation and calcination. Two types of phosphoric acids were used. The p H dependenc leaching test has been used as the basic characterization to evaluate the effect of the type of phosphori acid on the metals behavior in a valorization scenario. The standard leaching test and the Toxicit Characteristic Leaching Procedure(TCLP) were conducted as compliance tests. In regards of the obtaine results, the environmental assessment has also shown a reduction in the availability of targeted heav metals in alkaline environment whatever the type of acid used for treatment. This opens opportunitie for co-valorization.

关键词： Polluted sediments Heavy metals Phosphatation Calcination and environmental behaviour

Crystal structure and magnetic properties of SmCo_(6.6)Nb_(0.4) nanoflakes prepared by surfactant-assisted ball milling

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Journal of Rare Earths 2013年第10期31卷 975-978页

作者：潘蕊岳明张东涛高学绪刘卫强张久兴郭朝辉李卫 College of Materials Science and Engineering Beijing University of Technology State Key Lab of Advanced metals and Materials University of Science and Technology Beijing Division of Functional Materials Central Iron and Steel Research Institute

SmCo6.6Nb0.4 nanoflakes with TbCu7 structure were successfully prepared by surfactant-assisted high energy ball milling （sa-HEBM） with heptane and oleic acid as milling medium. The microstructure, crystal structure and magnetic properties were stud- ied by scanning electron microscopy, X-ray diffraction, and vibrating sample magnetometer, respectively. The effects of ball milling time on the c-axis crystallographic alignment and coercivity of the nanoflakes were systematically investigated. The research showed that the nanoflakes had an average thickness of 100 nm, an average diameter of 1 μm, with an aspect ratio as high as 100. As the ball milling time increased from 2 to 8 h, the reflection peaks intensity ratio I（002y/I（10l）, which indicated the degree of c-axis crystal texture of the SmCo6.6Nbo.4 phase, increased first, reached a peak at 4 h, and then decreased. Meanwhile, the coercivity of the nanoflakes also increased first, reached a peak at 13.86 kOe for 4 h, and then decreased.

关键词： SmCo6.6Nb0.4, nanoflakes high energy ball milling magnetic properties rare earths