JOURNAL OF ALLOYS AND COMPOUNDS
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2018
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IF 3.779
Longqing Chen,Bo Huang,Xiaoliang Yang,Youyun Lian,Xiang Liu,Jun Tang
Tungsten-potassium-titanium (W-K-Ti) alloys were fabricated by spark-plasma-sintering (SPS) and traditional rotary swaging (RS) techniques. Doping conditions and sintering methods were compared on the relative density, microstructure, hardness, recrystallization temperature, and the thermal shock resistance properties. Transient heat loads under 0.37 GW m −2 were applied on the W-K-Ti samples at room temperature for different cycles and pulsed durations. It was found that moderate Ti-doping (0.05 and 0.075 wt%) in W-K alloys can enhance the thermal shock resistance. Low-cycle thermal fatigue test suggested better thermal shock resistance in SPS-sintered W-K-Ti alloy (SPS-W-K-Ti) using TiH 2 dopant . The main reason was that the decomposition of TiH 2 significantly reduced the oxygen content of the ingots, which improved the ductility and thermal shock resistance of tungsten alloys . Further fracture analyses indicated that Ti-doping through TiH 2 formed intra- and inter- Ti-rich voids in TiH 2 -doped W-K alloy, while only intergranular Ti particles were found lying along grain boundaries in the Ti-doped one. The formation mechanism of the Ti-rich voids was investigated in detail. This work provides a potential route for obtaining plasma facing materials with high thermal shock resistance.
研究领域:
材料科学
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核能工程
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DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
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2022
·
IF 3.752
Zhao-wang DONG,Yang XIA,Xue-yi GUO,Qing-hua TIAN,Han-ning LIU,Pei-dong LIU,Yu-bing CHEN
A direct production method of high-strength titanium alloy from upgraded titania slag (UGS) was developed. First, UGS was reduced into alloy powder with 1.3 wt.% oxygen using magnesium powder. Subsequently, the alloy powder was compacted at 600 MPa to produce a pellet. Lastly, the pellet was sintered to produce titanium alloy. The reduced powder was characterized, and the effect arising from the sintering temperature on the sintered density, compressive strength, microstructure, and hardness of the alloys was studied. The results showed that the density tended to increase with the temperature increasing from 900 to 1200 °C, whereas the porosity decreased. A significant sintering densification was achieved at the temperature above 1100 °C (98.65% at 1100 °C and 99.41% at 1200 °C). At 1100 °C, the hardness and compressive strength reached the maximal values of the alloy, HV 655.7 and 1563 MPa, respectively.
研究领域:
材料科学
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冶金工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Mengjiao Jiao,Guishang Pei,Lilian Yang,Zhuoyang Li,Qiyuan Mi,Xuewei Lv
In the sodium-assisted smelting process of vanadium-titanium-magnetite (VTM), titanium oxide is hydrothermally separated by sulfuric acid solution leaching. Therefore, it is essential to study the dissolution behavior and mechanism of sodium titanates in sulfuric acid solution. High-purity Na 8 Ti 5 O 14 , Na 2 Ti 3 O 7 , and Na 2 Ti 6 O 13 samples were synthesized via solid-phase chemical reaction, and their solubilities of sodium titanates in 100 mL of 98 wt% sulfuric acid solution were determined. Na 8 Ti 5 O 14 , Na 2 Ti 3 O 7 , and Na 2 Ti 6 O 13 crystallize in the triclinic (space Group P -1), monoclinic (space Group P 2 1 / m ), and monoclinic (space Group C 2/ m ) system, respectively. The dissolution rate of sodium titanates in 98 wt% sulfuric acid solution increased significantly with rising reaction temperature. Among the sodium titanates studied, Na 8 Ti 5 O 14 showed the highest dissolution rate, followed by Na 2 Ti 3 O 7 and Na 2 Ti 6 O 13 . Kinetic analysis indicated that the dissolution behavior of sodium titanates in sulfuric acid was all governed by chemical reactions. The apparent activation energies of the dissolution reactions of Na 8 Ti 5 O 14 , Na 2 Ti 3 O 7 , and Na 2 Ti 6 O 13 with sulfuric acid were derived to be 49.48 kJ/mol, 53 kJ/mol, and 67.41 kJ/mol, respectively. The solubilities of Na 8 Ti 5 O 14 , Na 2 Ti 3 O 7 , and Na 2 Ti 6 O 13 in 100 mL of 98 wt% concentrated sulfuric acid at 20 ℃ were determined to be 18.6077 g, 7.3297 g, and 3.9948 g, respectively. Additionally, the dissolution rates and solubilities of sodium titanates and other impurities, such as aluminate and silicate, were compared, demonstrating the effectiveness of separation in sulfuric acid solution following the sodium-assisted smelting process of VTM. In this study, it is suggested that the separation of titanium oxide from other impurities during the sulfuric acid leaching of titanium-containing slag can be accomplished based on the varying solubilities of the phases.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
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IF 2.605
Yabing Zhang,Li Zhong,Dongping Duan
In the present study, strontium titanate (SrTiO 3 ) nanoparticles were successfully synthesized by a single-step direct hydrothermal process under the strong alkaline condition using crystalline anatase titanium dioxide (TiO 2 ) and strontium hydroxide octahydrate (Sr(OH) 2 ·8H 2 O) as the starting materials at 220 °C. The X-ray diffraction (XRD) patterns identified the products were highly crystalline and well matched with standard SrTiO 3 data. The crystalline structure, lattice parameters , and atomic position were refined by Highscore Plus and Maud program. The results of Rietveld refinement showed high purity of products. The thermal field emission scanning electron microscope and energy dispersive spectrometer (FE-SEM-EDS) displayed the samples prepared were perovskite phase cubic SrTiO 3 nanoparticles having regular morphology and small particle with a size distribution of 32–45 nm. The fine morphologies and structures of SrTiO 3 nanoparticles were investigated by field emission transmission electron microscope (FE-TEM). The results showed the important roles played by reaction duration and mole ratio of Sr and Ti (Sr/Ti) to the grain size of SrTiO 3 nanoparticles. The particle sizes increased with prolonging reaction duration and reducing Sr/Ti. Compared to SrTiO 3 synthesized by solid state reaction, the as-synthesized SrTiO 3 nanoparticles had large specific surface areas (up to 32.98 m 2 /g), which would exhibit potential applications in photocatalysis . The reaction mechanism of the process was illustrated using the dissolution–precipitation mechanism finally.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
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2024
·
IF 4.7
Jian PANG,Ling-xin KONG,Li-guo ZHU,Bao-qiang XU,Jun-jie XU,Chong-lin BAI,Bin YANG
A new method for the preparation of low oxygen titanium was proposed by the direct reduction of TiO 2 with Mg produced by MgCl 2 −KCl−YCl 3 molten salt electrolysis. The Mg−Ti−O phase diagram indicates that it is feasible to reduce TiO 2 using Mg, and the Φ − p O2− diagrams indicate that deep deoxidation of titanium in molten MgCl 2 −YCl 3 is also feasible. The experimental study on the reduction of TiO 2 was carried out in MgCl 2 −YCl 3 and MgCl 2 −YCl 3 −KCl molten salts. The results showed that the O 2− from the reduction and deoxygenation was removed using YOCl precipitation and CO x gas production and TiO 2 can be reduced to titanium peroxide (Ti 6 O) by electrochemical reduction at 1073−1173 K and 2.5−3.1 V. The high-oxygen titanium was electrochemically deoxidized in the molten salt of MgCl 2 −YCl 3 at a temperature of 1173 K at different voltages. Moreover, it was observed that it is possible to reduce the high oxygen content of titanium from 1200×10 −6 to less than 100×10 −6 oxygen.
研究领域:
材料科学
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冶金工程
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DOI
高影响因子
Nature Communications
·
2020
·Vol. 11
·期 1
·1-9
·
IF 12.121
Wang Jifei,Luo Shiqiang,Lin Yun,Chen Yifu,Deng Yehao,Li Zhimin,Meng Ke,Chen Gang,Huang Tiantian,Xiao Si,Huang Han,Zhou Conghua,Ding Liming,He Jun,Huang Jinsong,Yuan Yongbo
The manipulation of crystal orientation from the thermodynamic equilibrium states is desired in layered hybrid perovskite films to direct charge transport and enhance the perovskite devices performance. Here we report a templated growth mechanism of layered perovskites from 3D-like perovskites which can be a general design rule to align layered perovskites along the out-of-plane direction in films made by both spin-coating and scalable blading process. The method involves suppressing the nucleation of both layered and 3D perovskites inside the perovskite solution using additional ammonium halide salts, which forces the film formation starts from solution surface. The fast drying of solvent at liquid surface leaves 3D-like perovskites which surprisingly templates the growth of layered perovskites, enabled by the periodic corner-sharing octahedra networks on the surface of 3D-like perovskites. This discovery provides deep insights into the nucleation behavior of octahedra-array-based perovskite materials, representing a general strategy to manipulate the orientation of layered perovskites.
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
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2013
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IF 3.41
Cheng Liu,Jiale Huang,Daohua Sun,Yao Zhou,Xiaolian Jing,Mingming Du,Haitao Wang,Qingbiao Li
Anatase type extra-framework titanium in titanium silicate-1 (TS-1) molecular sieves has been observed to cause adverse catalytic impediments such as carbon–carbon bond cleavage and low H 2 O 2 efficiency during the epoxidation of terminal alkenes. In this study, a series of TS-1 sieves were synthesized, and used as catalysts for styrene epoxidation. Among the catalysts, the TS-1 with a Si/Ti molar ratio of 35 and 0.21 mol% of anatase type extra-framework titanium exhibited the best styrene conversion and styrene oxide (SO) selectivity. The results suggests that, framework Ti species have no effect on the stabilization of SO selectivity, whereas the synergetic interaction between the framework Ti species and the anatase type extra-framework titanium is essential for the outstanding catalytic performance of TS-1 in styrene epoxidation. In addition, our results demonstrate that the usage of tetraethyl orthosilicate (TEOS), tetrabutyl titanate (TBOT), and isopropyl alcohol in the synthesis of TS-1 does not guarantee the absence of extra-framework Ti species. Instead, the asynchronous degrees of hydrolysis between TEOS and TBOT might account for the formation of the anatase type extra-framework titanium. The influence of H 2 O 2 amount, reaction temperature and time, as well as the types of solvent, oxidant, and catalyst amount, on the catalytic performance of TS-1 with anatase type extra-framework titanium was likewise investigated.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
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2022
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IF 6.044
Zeyun Cai,Tao Xiang,Weizong Bao,Jiayin Chen,Tian Gao,Guoqiang Xie
Pure titanium is an ideal material for tissue replacements and implant materials for its superior biocompatibility and corrosion resistance , but its limited strength remains a major obstacle to its wide applications. A promising strategy for enhancing the strength is to alloy the pure titanium with oxygen. Herein, we reported an oxygen solid solution strengthening for pure titanium by achieving a titanium-oxygen (Ti–O) alloy using ball milling (BM) and spark plasma sintering (SPS). The effect of oxygen contents, ranging from 0.33 to 2.08 wt%, on the mechanical properties of pure titanium was systematically investigated. Experimental results indicate that the Ti–O alloy with the oxygen content of 1.95 wt% reached an ultrahigh yield strength of 2026 MPa and showed a large ductility of 11.2% in compression. According to the quantified analysis of strengthening mechanisms, solid solute oxygen atoms are responsible for the balance of superior yield strength and ductility of the Ti–O alloys.
研究领域:
材料科学
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生物医学工程
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DOI
高影响因子
RSC Advances
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2015
·Vol. 6
·期 4
·2778-2784
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IF 3.84
Yaoming Xiao,Gaoyi Han,Haihan Zhou,Jihuai Wu
A titanium (Ti) foil based perovskite solar cell (PSC) is devised and prepared by employing titanium dioxide nanowire (TNW) arrays and titanium dioxide nanoparticles (TNPs) on Ti foil substrates as the electron transporting layer (ETL). The TNW array is desirable for the PSC, since it can provide direct pathways for the rapid collection and transmission of photo-generated electrons. The Ti foil substrate has many advantages such as flexibility, low sheet resistance, and excellent mechanical stability. The sunlight illuminates through the highly transparent poly(3,4-ethylenedioxythiophene) (PEDOT) film on the indium doped tin oxide/polyethylene naphthalate (ITO/PEN) substrate. The transparent PEDOT electrode can be used as the hole transporting layer (HTL) due to the well matched band positions for charge separation and transport. As a result, the Ti foil based light-weight PSC with TNW arrays yields an efficiency of 13.07% with an active area of 1.00 cm2, which is higher than that of the PSC with TNPs (9.93%). These promising results highlight the potential application of the PEDOT and Ti foil in cost-effective, large-area, and flexible PSCs.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-13
·
IF 15.7
Huang Jun,Yang Qirui,Hu Anyi,Liao Zhu,Zhang Zhengxi,Zheng Qinfeng,Ren Zhouhong,Zheng Shun,Zhang Yixiao,Yang Xiaolong,Xu Zhenming,Zhang Le,Zhu Daming,Wen Wen,Liu Xi,Orita Akihiro,Saito Nagahiro,Wang Liguang,Xia Yongyao,Chen Liwei,Lu Jun,Yang Li
Developing lithium-ion batteries with high specific energy and fast-charging capability requires overcoming the potential-capacity trade-off in negative electrodes. Conventional fast-charging materials (e.g., Li 4 Ti 5 O 12 , TiNb 2 O 7 ) operate at high potentials (>1.5 V vs. Li + /Li) to circumvent lithium plating, yet this compromises specific energy. A viable strategy for enhancing the specific energy is to reduce the potential while avoiding the lithium plating risk; however, the underlying mechanisms remain unclear. Here we demonstrate that enhancing Titanium-Oxygen covalency through pseudo-Jahn-Teller Effect distortion in Ruddlesden-Popper perovskites enables low-potential operation. The Li 2 La 2 Ti 3 O 10 negative electrode exhibits a working potential of 0.5 V vs. Li + /Li with initial 139.3 mAh g −1 at 5 A g −1 and 72.9% capacity retention after 5000 cycles. Full cells with LiNi 0.8 Co 0.1 Mn 0.1 O 2 positive electrodes deliver 3.45 V average discharge voltage-50% higher than conventional Li 4 Ti 5 O 12 | |LiNi 0.8 Co 0.1 Mn 0.1 O 2 systems-achieving 100 mAh g −1 at 4 A g −1 . Mechanistic analysis reveals low Li⁺ migration barriers and stable Ruddlesden-Popper perovskite frameworks enable rapid ion transport.
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DOI
PubMed
高影响因子
Journal of Sustainable Metallurgy
·
2023
·Vol. 9
·期 3
·1303-1314
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IF 2.4
Lv Ningning,Qiu Yuchao,Hu Yiming,Shi Hangkai,Shi Junjie,Ding Xiang,Li Haolun
It has been proved that Cr 2 O 3 is favorable to promote the crystallization of perovskite in the Selective Crystallization and Phase Separation (SCPS) process. However, the related thermodynamic data of equilibrium phase relations was quite limited. In the present work, the equilibrium phase relations of CaO-SiO 2 -TiO 2 system with the addition of 5 wt% Cr 2 O 3 were experimentally carried out using the high temperature equilibration-quenching technique followed by X-Ray Diffraction (XRD), Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM–EDS), as well as thermodynamic calculation. More attention has been focused on the influence of 5 wt% Cr 2 O 3 addition on the liquid-perovskite two-phase coexisting region. The results indicated that the crystallization of perovskite was promoted by Cr 2 O 3 addition by expanding the primary phase of perovskite toward higher SiO 2 areas. Meanwhile, distinct discrepancies were found when the present experimental results were compared with the data from the literature and the isotherms calculated by FactSage, indicating that the present results are not only meaningful for the improvement of the SCPS process, but also important for the optimization of titania related oxide thermodynamic database. Graphical Abstract
研究领域:
冶金学
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材料科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Hongzhan Lv,Liwen Zhang,Xiaoli Xi,Zuoren Nie
With the widespread expansion of titanium applications and its significant increase in usage, the issue of recycling titanium resources after consumption has emerged. Focusing on titanium alloys with high usage, such as TC4 (Ti-6Al-4V), this article proposes a titanium separation and recovery method based on molten salt electrolysis. This method thoroughly analyzes the characteristics of elements in TC4 and electrochemical principles, ensuring that vanadium in the TC4 alloy does not undergo electrochemical dissolution when the electrolysis potential is below 0.3 V vs Pt. Subsequently, through electrochemical analysis, it was discovered that the precipitation of aluminum ions is influenced by concentration. Therefore, by controlling the concentration of aluminum in the eutectic molten salt, such as increasing the electrolyte concentration and shortening the electrolysis time, the precipitation of aluminum can be effectively avoided. Under the experimental conditions mentioned above, vanadium elements deposit at the bottom of the crucible in the form of anode slime, while aluminum dissolves and remains in the electrolyte. Meanwhile, titanium ions in the cathode region undergo electron reduction and deposit in the cathode area in the form of titanium, thus achieving precise separation of alloy elements. Experimental verification shows that the purity of the obtained titanium reaches 99.17 atomic percent. Therefore, this molten salt electrolysis method, which combines the physical properties of alloy elements with electrochemical principles, not only provides a new perspective for the separation and recovery of titanium and other critical metals, but also offers new research directions for the recovery technology of other alloy elements.
研究领域:
冶金学
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材料科学
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电化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）