ISSN 1005-3093
CN 21-1328/TG
Started in 1987

About the Journal

  Current Issue
    , Volume 32 Issue 9 Previous Issue    Next Issue
    For Selected: View Abstracts
    研究论文
    Influence of H2 Flow Rate on Structure and Erosion Resistance of Thermal Barrier Coatings Prepared by Plasma Spray-Physical Vapor Deposition
    Fei LIU, Min LIU, Jie MAO, Ziqian DENG, Jingtao MA, Changguang DENG, Dechang ZENG
    Chinese Journal of Materials Research, 2018, 32 (9): 641-646.  DOI: 10.11901/1005.3093.2017.347
    Abstract   HTML   PDF (3500KB) ( 367 )

    Different thermal barrier coatings (TBCs) of ZrO2-7%Y2O3 (7YSZ) were prepared on high temperature alloy K417 by plasma spray-physical vapor deposition (PS-PVD) processes with changing H2 flow rate for the plasma gas, while the influence of H2 flow rate on the structure and erosion resistance of TBCs was investigated. Results show that the H2 flow rate of plasma gas presents significantly influence on the surface topography, structure, porosity, hardness, and erosion resistance of the prepared PS-PVD TBCs. When the H2 flow rate is 0, 5 and 10 SLPM (standard liter per minute) respectively, the corresponding TBCs present the following properties: 16.7%, 20.4% and 7.7% for porosity; 224.2 HV0.025, 236.6 HV0.025 and 394.4 HV0.025 for hardness; and 78.5 mg, 65.0 mg and 17.3 mg for mass loss after solid particles erosion test for 25 s. With the increase of H2 flow rate, the porosity of PS-PVD TBCs increases at first and then decreases, while the hardness and erosion resistance increase.

    Figures and Tables | References | Related Articles | Metrics
    Influence of the γ' -phase Morphology on Portevin-Le Chatelier Effect in a Ni-Co Base Superalloy
    Guoliang ZHANG, Xinguang WANG, Daohong WANG, Zhihai LI, Hongbin YAN, Chuanyong CUI
    Chinese Journal of Materials Research, 2018, 32 (9): 647-654.  DOI: 10.11901/1005.3093.2017.524
    Abstract   HTML   PDF (7036KB) ( 360 )

    A Ni-Co based alloy with γ' -phase of various morphologies was prepared by different heat treatment processes. Then the influence of the γ' -phase on the Portevin-Le Chatelier (PLC) effect was investigated systematically. Results show that the PLC effect is related to the morphology of the γ' -phase. During tensile test the alloy shows large stress drop while the spherical-shaped γ' -phase existed. The γ' -phase with flowery and cubic morphology would accelerate the transformation from normal PLC to inverse PLC. When the alloy was tensile tested in medium-low temperatures (400, 500°C) the dislocations would pile up around the γ' -phase with flowery and cubic morphology, and the deformation mechanism of the alloy may be described mainly to stacking fault or deformation twin. While less dislocation piled up around the spherical-shaped γ' -phase, therefore, the deformation of the alloy is mainly controlled by the dislocation slip.

    Figures and Tables | References | Related Articles | Metrics
    Effect of B and Ru Co-modification on Structure and Photocatalytic Activity of TiO2 Nanotubes
    Zhumei WANG, Xiaoling ZHU, Yueming LI, Runhua LIAO, Zongyang SHEN, Jianlin ZUO
    Chinese Journal of Materials Research, 2018, 32 (9): 655-661.  DOI: 10.11901/1005.3093.2017.522
    Abstract   HTML   PDF (3650KB) ( 341 )

    TiO2 nanotube arrays (TNTs) and boron doped TiO2 nanotube arrays (B/TNTs) on Ti-foil were prepared via anodic oxidation process in electrolyte composed of ethylene glycol, H2O and NH4F, without and with addition of NaBF4 respectively. Then TNTs and B/TNTs were further impregnated in Ru2+ containing solution to fabricate Ru-modified TiO2 nanotube arrays of Ru/TNTs and Ru/B/TNTs. The prepared products were characterized by multi-functional field-emission scanning electron microscope (FE-SEM), energy dispersive spectrometer (EDS), X-ray diffractometer (XRD), UV-visible diffuse-reflectance spectrum (UV-Vis DRS) and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of the products was examined via degradation test of methylene blue solution under visible light irradiation. Results show that B was incorporated into the TNTs lattice to form B-O-Ti bond and Ru was introduced to form RuO2 on the surface of Ru/TNTs. However, the main part of Ru formed as RuO2 deposited on the surface of B/TNTs. On the contrary, for Ru/B/TNTs there exist a large amount of Ru0 and small amount of RuO2 in the surface deposits and whilst very little Ru incorporated into the TNTs lattice; B-doping could effectively raise the the number of hydroxyl groups on the surface of B/TNTs, decrease the band gap energy and make the red shifting of absorption edges of the B/TNTs, which induce the significant increasing of the photocatalytic activity of B/TNTs. For the Ru/TNTs, the deposit of RuO2 could not lead to the increase of the number of hydroxyl groups on the surface of Ru/TNTs but would decrease the band gap energy and make the red-shifting of the absorption edges, eventually promoting the photocatalytic activity of Ru/TNTs to some extent. By comparison with B/TNTs, the surface of Ru/B/TNTs is rich in Ru0, which could increase the band-gap energy, thus induce the blue shifting of the absorption edges, which eventually induces a lower photocatalytic activity of Ru/B/TNTs (similar to pure TiO2 nanotubes).

    Figures and Tables | References | Related Articles | Metrics
    Mechanical Property and Precipitation of 900 MPa Grade Hot-rolled TRIP Steel
    Xutao GAO, Aimin ZHAO, Yuan ZHANG
    Chinese Journal of Materials Research, 2018, 32 (9): 662-668.  DOI: 10.11901/1005.3093.2017.326
    Abstract   HTML   PDF (4997KB) ( 376 )

    The precipitation behavior and mechanical property of hot-rolled TRIP steel C-Si-Mn-Nb-V-N coiled at two different temperatures were investigated by means of XRD, TEM and tensile test. Results show that the size of precipitates is smaller, while the quantity of the precipitates is larger for the steel coiled at 450℃ rather than at 400℃. The average grain size of ferrite grains of the steel coiled at the two temperatures is all less than 5 μm, but the difference in quantities of retained austenite grains is small. The tensile strength and strength-ductility product of the steel coiled at 450℃ are 900 MPa and 27000 MPa∙% respectively, which may be ascribed to both of the fine grain strengthening and precipitation strengthening. Therefore, the steel coiled at 450℃ presents better comprehensive mechanical property than that coiled at 400℃.

    Figures and Tables | References | Related Articles | Metrics
    Effect of Cu on Electrocatalytic Oxidation of Ethanol by Catalyst Pdx-Cu/C
    Limei SUN, Suriguga LI, Lele SHI, Yijia ZHANG
    Chinese Journal of Materials Research, 2018, 32 (9): 669-674.  DOI: 10.11901/1005.3093.2017.688
    Abstract   HTML   PDF (2471KB) ( 345 )

    Catalysts of Pdx-Cu/C with different ratios of Pd to Cu on carbon (Vulcan XC-72) were prepared by an improved chemical reduction method, which then were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electrochemical methods in terms of the morphology and catalytic performance of the catalysts. Especially, the effect of Cu on the catalytic performance of Pd/C catalysts was investigated. Results show that the catalytic activity of the catalysts of Pdx-Cu/C increased first and then decreased with the increasing ratios of Pd to Cu. When Pd:Cu=8:1, catalyst particles of Pd8-Cu/C were uniformly dispersed on the surface of the carbon carrier, and the diameter of the catalyst is about 2.8 nm. A small amount of Cu atoms entered the Pd lattice and formed a PdCu alloy. In 1 mol/L KOH solution the catalyst Pd8-Cu/C showed the best catalytic activity and stability that the peak current density of C2H5OH oxidation on Pd8-Cu/C reached 114 mA/cm2, which was 2.5 times of that on Pd/C and 3.6 times of that on JM-Pd/C respectively.

    Figures and Tables | References | Related Articles | Metrics
    Superplastic Behavior and Deformation Mechanism of 7B04 Al-alloy
    Jian WANG, Wenjing YANG, Zhuoliang LI, Hua DING, Ning ZHANG, Hongliang HOU
    Chinese Journal of Materials Research, 2018, 32 (9): 675-684.  DOI: 10.11901/1005.3093.2018.105
    Abstract   HTML   PDF (6811KB) ( 303 )

    Superplastic tensile tests were carried out for 7B04 Al-alloy at 470~530℃ with initial strain rates within a range of 3×10-4 s-1 to 1×10-2 s-1. Among others the alloy presents the maximum elongation of 1663% at 530℃with the initial strain rate 3×10-4 s-1. Calculation results showed that the maximum strain rate sensitivity index m was 0.63 and the deformation activation energy Q were 158.44 kJ/mol, 188.13 kJ/mol, 177.78 kJ/mol, and 250.54 kJ/mol respectively corresponding to initial strain rates 1×10-2 s-1, 3×10-3 s-1 and 1×10-3 s-1, 3×10-4 s-1. A constitutive equation was established to describe the hot deformation behavior. The R-W-S deformation mechanism maps of the alloy were established. The superplastic deformation mechanism was analyzed by considering the microstructure evolution and the calculation results. It follows that the superplastic deformation mechanism of the 7B04 Al-alloy is mainly the dislocation slip accommodated grain boundary sliding controlled by lattice diffusion.

    Figures and Tables | References | Related Articles | Metrics
    Degradation of Formaldehyde Gas by Composites of La-doped Nano ZnO/diatomite
    Xie LI, Xiaodong ZHU, Tingting WANG, Hui WANG
    Chinese Journal of Materials Research, 2018, 32 (9): 685-690.  DOI: 10.11901/1005.3093.2018.114
    Abstract   HTML   PDF (3672KB) ( 310 )

    A series of ZnO nanoparticles doped with different La-content were synthesized by two-phase interface method. Then the surface of ZnO nanoparticles was activated by trichloroacetic acid, and finally, the composite of modified ZnO/diatomite was prepared by using sol gel technology. The nanoparticles were characterized by Fourier transform infrared (FTIR) spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TG) and other techniques. Results show that in comparison to the composite with the blank nano-ZnO, the degradation of formaldehyde induced by the composite with the La doped nano-ZnO in the visible region has been greatly improved.

    Figures and Tables | References | Related Articles | Metrics
    Influence of Co and Ni on Invar Effect of (Fe71.2B24Y4.8)96Nb4 Bulk Metallic Glass
    Jinmiao WANG, Qiang HU, Yihong YAN, Caosheng HU, Shenghui XIE, Xierong ZENG
    Chinese Journal of Materials Research, 2018, 32 (9): 691-696.  DOI: 10.11901/1005.3093.2018.115
    Abstract   HTML   PDF (1142KB) ( 271 )

    Thermal expansion behavior of bulk metallic glasses [(Fe100-xCox)71.2B24Y4.8]96Nb4 (x=0~60) and [(Fe100-xNix)71.2B24Y4.8]96Nb4 (x=0~20) was investigated. Results show that the Invar effect of the (Fe71.2B24Y4.8)96Nb4 decreases after the addition of Co or Ni, and the decreasing extent is almost the same if the amount of x is the same for Co and Ni respectively. These phenomena indicate that the decreasing amount of the Fe-Fe atomic pairs is the main influence of Co and Ni on the Fe atomic local structure. In addition, the thermal expansion coefficient after the magnetic transition changes oppositely with the Curie temperature, which is mostly related to the free volume annihilation in the structural relaxation.

    Figures and Tables | References | Related Articles | Metrics
    Effect of Cu Content on Fluidity of Mg-7Zn-0.6Zr Alloys
    Ye ZHOU, Pingli MAO, Boshen YANG, Zhi WANG, Le ZHOU, Zheng LIU, Feng WANG
    Chinese Journal of Materials Research, 2018, 32 (9): 697-705.  DOI: 10.11901/1005.3093.2018.352
    Abstract   HTML   PDF (5849KB) ( 306 )

    Mg-Zn-Cu ternary alloys were draw much attention in recent years for its good high temperature performance. However, the fluidity plays a key role in the castability of Mg alloys. Therefore, the hot tearing susceptibility of Mg-7Zn-xCu-0.6Zr (x=0,1,2,3) alloys was investigated by means of a home-made mould for casting fluidity measurement and cooling curve thermal analysis. The microstructure and phase constituents of Mg-7Zn-xCu-0.6Zr (x=0,1,2,3) alloys were characterized by means of TEM, SEM,EDS and EPMA. Results show that with the increasing of Cu content, the dendrite coherence temperature (Tcoh) and the solidification interval decreased, while the grain size was refined. With the addition of Cu a new low-melt eutectic phase formed, and the fluidity of Mg-7Zn-xCu-0.6Zr (x=0,1,2,3) were improved.

    Figures and Tables | References | Related Articles | Metrics
    Preparation and Property of Proton Exchange Membranes Synthesized via One-step Grafting PSPMA onto Poly(vinylidene fluoride) Modified by TMAH
    Qiang HUANG, Guibao GUO, Shengli AN, Jinyan LIU
    Chinese Journal of Materials Research, 2018, 32 (9): 706-712.  DOI: 10.11901/1005.3093.2018.112
    Abstract   HTML   PDF (2136KB) ( 466 )

    Methanol solution of tetramethylammonium hydroxide (TMAH) modified poly(vinylidene fluoride) (PVDF) was directly grafted with poly (sulfopropyl methacrylate) via a one-step process to synthesis proton exchange membranes of (PVDF-g-PSPMA). The microstructures, morphologies, and distributions of sulfur in the membrane were characterized using Fourier transform infrared spectroscope (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The influence of the TMAH on proton conductivity and methanol permeability of these membranes were also investigated. Results show that PVDF was dehydrofluorinated by TMAH and produced carbon-carbon double bond. SPMA was successfully grafted onto PVDF, the distribution of sulfur was homogeneous in the interior and surface of the membrane. The proton conductivity and methanol permeability coefficient of the membrane increase with the content of TMAH, and when the content of TMAH was 20% the proton conductivity of membrane was 8.39×10-2 S∙cm-1 at ambient temperature, and the methanol permeability coefficient was 8.92×10-7 cm2∙s-1. Thermo gravimetric analysis (TGA) confirmed that the membranes possess good thermal stability up to approximately 270℃. The peak power density of direct methanol fuel cell (DMFC) assembled with above membrane was 18.87 mW∙cm-2.

    Figures and Tables | References | Related Articles | Metrics
    Synthesis and Li-storage Performance of Hierarchical Spheroid Composites of MgFe2O4/C
    Rongzhen GAO, Xiaodong LI, Wenfeng LIU, Yanhong YIN, Shuting YANG
    Chinese Journal of Materials Research, 2018, 32 (9): 713-720.  DOI: 10.11901/1005.3093.2017.795
    Abstract   HTML   PDF (5795KB) ( 349 )

    The spherical composite of MgFe2O4/C (MFO/C) with hierarchical structure was prepared via spray drying technology with citric acid and Super P (SP) as carbon source. The morphology, structure and electrochemical performance of the MFO/C were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray powder diffractometer (XRD), X-ray photoelectron spectrometer (XPS) and electrochemical measurements. Results show that the first discharge capacity of the material is 1162.7 mA∙g-1 and the reversible specific capacity stabilizes at about 734.5 mA∙g-1 after 200 cycles when the current density is 0.5 C (500 mA∙g-1). Even at a higher current density of 1 C (1000 mA∙g-1), the reversible specific capacity stabilizes at about 580.4 mA∙g-1 after 200 cycles. The excellent cycling stability and rate performance can be attributed to the emerging of a superior conductive network, which composed of SP and the intergranular carbon formed due to the decomposition of citric acid, as a result, the conductivity of the spherical composite of MgFe2O4/C could be effectively enhanced, while the aggregation and volumetric expansion of the active particles could also be alleviated in the continuous charge and discharge process.

    Figures and Tables | References | Related Articles | Metrics