MATERIALS TRANSACTIONS
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ONLINE ISSN: 1347-5320
PRINT ISSN: 1345-9678

MATERIALS TRANSACTIONS Vol. 58 (2017), No. 5

  • Performance of Alkali-Resistant Glass Fibers Modified with Refused Coal Ore

    pp. 705-710

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    DOI:10.2320/matertrans.M2016321

    In this study, we fabricated E-glass fibers and alkali-resistant (AR)-glass fibers with a 7 mass% zirconia content, and AR-glass fibers with a 7 mass% zirconia and 30–50 mass% refused coal ore content. The obtained fibers were characterized for their tensile strength and alkali-resistant properties after dipping the fibers in an alkaline solution. The alkali test results, based on microscopic images, showed that the AR-glass fibers with 7 mass% zirconia and 40 mass% refused coal ore had better chemical resistance than the E-glass fibers. The average tensile strengths of the E-glass fibers and the AR-glass fibers with 7 mass% zirconia and 40 mass% refused coal ore, after being dipped in an alkaline solution for 48 h, were 240 and 343 MPa, respectively. In addition, after an alkali test for 72 h, the average tensile strength of AR-glass fibers with 7 mass% zirconia was 277 MPa, and the average tensile strength of AR-glass fibers with 7 mass% zirconia and 40 mass% refused coal ore was 296 MPa. The AR-glass fibers with a high tensile strength and low fiberizing temperature, fabricated using refused coal ore, can be widely used as alkali-resistant glass fibers.
  • Microstructure and Mechanical Properties of Friction-Welded A6063 and A2017 Alloys

    pp. 711-715

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    DOI:10.2320/matertrans.M2017004

    The microstructures and mechanical properties of lightweight friction-welded dissimilar materials such as A6063 and A2017 alloy rods were investigated in this study. Friction welding was performed at a rotation speed of 2,000 RPM, friction load of 12 kgf/cm2, and upset force of 25 kgf/cm2. After welding, grain boundary characteristic distributions and the formation of intermetallic compounds were analyzed by electron backscattering diffraction and transmission electron microscopy, respectively, while the mechanical properties of the welded materials were studied by Vickers microhardness and tensile testing. The obtained results revealed that the friction welding of the two alloys led to significant grain refinement from around 50 μm for the base materials to 2 μm for the welded zone, while the Vickers microhardness and tensile strength of the welded area were equal to 81% and 96% of the corresponding values for the base materials, respectively, owing to the formation and growth of intermetallic compounds. However, the fracture initiated in the A6063 base material during tensile testing indicated superior quality of the welded joint. Therefore, friction welding of dissimilar materials can be effectively used to produce joints with high durability.
  • Temperature Dependence of the Magnetic Hysteresis Curves in Magnetic Multilayers

    pp. 716-719

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    DOI:10.2320/matertrans.M2016348

    We performed a theoretical study of the magnetic hysteresis curves for an Fe3O4-based magnetic multilayer. Such a systems are known as the spin valves in the spintronics field. To investigate the temperature dependence of the magnetization process in such a system, we extend the retarded trace method and plot the magnetic hysteresis curve by computer simulation. Our results show very good agreement with the experimental data.
  • Enhancement of the Phase Formation Rate during In-Field Solid-Phase Reactive Sintering of Mn-Bi

    pp. 720-723

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    DOI:10.2320/matertrans.MBW201609

    Microstructural analysis was performed for Mn-Bi prepared by in-field solid-phase reactive sintering, in order to investigate the origin of magnetic field effects on the reaction. The number of formed MnBi phase around Mn grain in 10 T was almost 3 times larger than that in a zero field. The results indicated that the magnetic field enhanced the phase formation rate of MnBi phase. Due to the enhancement of the phase formation rate, the fraction of MnBi phase was drastically increased by in-field annealing.
  • Enhanced Hydrogen Generation Properties of Al-Ga-In-Sn Alloy in Reaction with Water by Trace Amount of AlTi5B Additives

    pp. 724-727

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    DOI:10.2320/matertrans.M2016425

    Al-3Ga-3In-Sn (mass%) alloy with a little amount of AlTi5B as refiner was fabricated using a simple smelting and casting method. The phase compositions and microstructure were investigated by means of XRD and SEM with EDX. The hydrogen generation property of Al-Ga-In-Sn alloy with water was investigated. The results show that the Al grains and GIS (Ga-In-Sn) particles are refined and more uniform with adding AlTi5B to Al-Ga-In-Sn alloy. Al grains size decrease from 120 μm to 40 μm and the GIS particles are refined to 1 μm respectively. The hydrogen generation rate of Al-3Ga-3In-Snalloy with 0.1 mass%AlTi5B reaches 44 mL/min g at 30℃, and 460 mL/min g at 60℃, which is much higher than that of Al-3Ga-3In-Sn alloy. The high hydrogen generation rate is ascribed to the Al grain refinement and increasing amounts of GIS particle.
  • Improvement of Strength–Elongation Balance of Al–Mg–Si Sheet Alloy by Utilising Mg–Si Cluster and Its Proposed Mechanism

    pp. 728-733

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    DOI:10.2320/matertrans.M2016258

    The tensile properties of an Al–Mg–Si alloy with Mg–Si clusters were compared with those of an Al–Mg–Si alloy with β″ precipitates of the same strength. The elongation of the alloy with Mg–Si clusters was found to be greater than that of the alloy with β″ precipitates because of the high work hardening rate of the former alloy, particularly in the high-strain region. Decomposition of Mg–Si clusters into solute Mg and Si atoms during the tensile deformation was revealed by differential scanning calorimetry. Transmission electron microscopy revealed three types of dislocation characteristics in these alloys: homogeneous distribution of dislocations with β″ precipitates, cell structures in the alloy with solute Mg and Si, and a combination of these two types in the alloy with Mg–Si clusters. In the case of the alloy with Mg–Si clusters, the yield strength increased significantly owing to the dislocation cutting mechanism; simultaneously, the elongation of this alloy improved greatly because of the presence of solute Mg and Si atoms formed by decomposition via plastic deformation, which were inferred to prevent dynamic recovery in the later stage of tensile deformation. Consequently, a comparison of conventional 6000 series and 7000 series Al alloys revealed that the alloy with clusters had advantages over the alloy with precipitates and the alloy with solutes in terms of the balance between strength and elongation. This Paper was Originally Published in Japanese in J. Japan Inst. Met. Mater. 79 (2015) 391–397.
  • Effect of TiB2 on Microstructure of 7075 Al Alloy Semi-Solid Slurry at Different Solid Fraction

    pp. 734-738

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    DOI:10.2320/matertrans.M2016458

    TiB2/7075 Al matrix composites were fabricated by in situ reaction, and the effect of TiB2 particle content on the microstructure of 7075 Al alloy slurry in semi-solid state at different solid fraction were investigated. The results showed that the grain sizes of TiB2/7075 Al matrix composites firstly decreased then increased and finally decreased again with the increase of TiB2 content because the role of particles shifted from dominating by locating to dominating by nucleation as the quantity of TiB2 particles increased due to the decrease of the mean diameter of TiB2 particles. As the holding time increasing in the semisolid state, dendritic grains were necked and remelted at first, then rosette grains melted and shrank into the globular grain, finally the globular grains began to grow, but the number of grains decreased and their mean grain size increased. The minimum grain size of 3.0, 4.5 and 9.0%TiB2/7075 Al matrix composites slurry were 81 μm, 51 μm and 69 μm after holding for 35, 20 and 50 mins at 630℃, respectively. The minimum grain size of 3.0 and 4.5%TiB2/7075 Al matrix composites slurry were 100 μm and 75 μm after holding for 120 and 90 mins at 620℃, respectively. However, the maximum size of globular grains was not associated with the TiB2 particle content, the maximum grain sizes of 3.0%TiB2/7075 and 4.5%TiB2/7075 Al matrix composites slurry at 620℃ were approximately 128 μm.
  • Ion Species/Energy Dependence of Irradiation-Induced Lattice Structure Transformation and Surface Hardness of Ni3Nb and Ni3Ta Intermetallic Compounds

    pp. 739-748

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    DOI:10.2320/matertrans.MBW201612

    Bulk samples of Ni3Nb and Ni3Ta intermetallic compounds were irradiated with 16 MeV Au, 4.5 MeV Ni, 4.5 MeV Al, 200 MeV Xe and 1.0 MeV He ions, and the change in near-surface lattice structure was investigated by means of the grazing incidence x-ray diffraction (GIXD) and the extended x-ray absorption fine structure (EXAFS). The Ni3Nb and Ni3Ta lattice structures transform from the ordered structures (orthorhombic and monoclinic structures for Ni3Nb and Ni3Ta, respectively) to the amorphous state by the Au, Ni, Al and Xe ion irradiations. Irrespective of such heavy ion species or energies, the lattice structure transformation to the amorphous state almost correlate with the density of energy deposited through elastic collisions. In the case of the samples irradiated with 1.0 MeV He ions, however, no amorphization was observed even when the density of elastically deposited energy is the same as that for Au irradiated sample which showed the amorphous phase. The change in Vickers hardness induced by the amorphization was also measured and was discussed in terms of ion fluence and the density of deposited energy.
  • Evaluation of Ion-Irradiation Hardening of Tungsten Single Crystals by Nanoindentation Technique Considering Material Pile-Up Effect

    pp. 749-756

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    DOI:10.2320/matertrans.M2016437

    Ion-irradiation hardening of pure tungsten (W) single crystal was evaluated by nanoindentation (NI) technique considering material pile-up effect. Pure W single crystals of (001) surface orientation were ion-irradiated with 6.4 MeV Fe3+ to 0.1 dpa, 1 dpa or 2 dpa at 573 K. The irradiation hardening was evaluated by means of NI measurements with elastic-modulus-based correction (EMC) method [C. Heintze et al.: J. Nucl. Mater. 472 (2016) 196–205]. The effect of material pile-up in tungsten was so significant that the bulk equivalent hardness values by EMC method were about 70% and 85% of uncorrected results for irradiated and unirradiated W(001), respectively. The ion-irradiation hardening values by EMC based method were approximately 40%, 50% and 60% of uncorrected results for 0.1 dpa, 1 dpa and 2 dpa, respectively. The measured maximum pile-up height was higher for irradiated W(001) than for unirradiated W(001) at each indentation depth. An averaged pile-up height that was associated with the actual area of contact of pile up obtained from EMC hardness showed different responses to ion-irradiation depending on the indentation depth.
  • Effect of Shot Peening on Mechanical Behavior of Zr-Based Bulk Metallic Glasses under Monotonic and Cyclic Loading Mode

    pp. 757-760

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    DOI:10.2320/matertrans.M2016349

    The mechanical behavior of as-cast and peened (Zr55Cu30Ni5Al10)99Y1 bulk metallic glass (BMG) under monotonic loading and cyclic loading mode was investigated. Abundant pre-existing shear bands were observed on the surface of the BMG after shot peening. It is suggested that shot peening can significantly enhance the compressive plasticity of the BMG. Interestingly, compared with the as-cast specimen, the peened specimen exhibits the similar yield stress of about 1850 MPa and fatigue limit of about 1095 MPa in stress range, but shorter fatigue life at high stress level. That is to say, shot peening has a great influence on the fatigue properties of BMG in high stress range, and has little influence on the fatigue properties of BMG in low stress range near fatigue limit. This is attributed to mutually competition between the positive effect and negative effect on the mechanical behaviors of BMG induced by shot peening, and which one of the two effects plays the dominant role depends mainly on the loading mode. The present study will give suggestion for the safe service of Zr-based BMG.
  • Electrolysis Oxidation of Chalcopyrite and Molybdenite for Selective Flotation

    pp. 761-767

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    DOI:10.2320/matertrans.M-M2017807

    Electrolysis oxidation of chalcopyrite and molybdenite was investigated, via various electrochemical methods, with the aim of realizing selective flotation of these minerals. Result of potential polarization indicated that oxidation via electrolysis affected only the chalcopyrite surface, owing mainly to the difference in conductivity of these minerals. Also measurements of contact angle after electrolysis indicated that contact angle of chalcopyrite selectively decreased whereas that of molybdenite did not decrease drastically. XPS analyses after electrolysis indicated that chalcopyrite peak decreased whereas iron oxyhydroxide (goethite) and iron sulfate increased, it suggests that these oxidation products covered on the surface of chalcopyrite. On the other hand, molybdenite peak is similar after electrolysis except for molybdenum oxide/oxygen with molybdenite can be seen for oxygen peak. From these results and general knowledge that sulfide hydrophobicity and sulfate/oxyhydroxide hydrophilicity, it can be explained that with electrolysis oxidation, hydrophilic oxihydroxide and sulfate covered on the surface of hydrophobic chalcopyrite then chalcopyrite surface became hydrophilic. On the other hand, molybdenite surface keep hydrophobic since its difficulty of oxidation and it is difficult to stay molybdenum oxide on the surface due to its soluble property. These results revealed that chalcopyrite was selectively oxidized and, hence, selective flotation of chalcopyrite and molybdenite was possible. This electrolysis oxidation methods were compared with those governing other oxidation treatments.
  • Mechanism of Intergranular Corrosion of Brazed Al–Mn–Cu Alloys with Various Si Content

    pp. 768-775

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    DOI:10.2320/matertrans.L-M2017808

    This study investigated the effect of post-brazing cooling rate and Si addition on the intergranular corrosion (IGC) susceptibility of brazed Al–Mn–Cu alloys by electrochemical analysis and microstructure observation. Water-quenched samples after brazing exhibited no IGC susceptibility, whereas slowly-cooled samples were prone to IGC. The results suggest that IGC is caused by precipitation during cooling. In addition, it was observed that IGC susceptibility depended on the Si content. An alloy sample with a low Si-additive content exhibited high IGC susceptibility because Mn/Cu-depleted zone was formed near the grain boundaries as a result of the preferential precipitation of Al6(Mn,Fe) and CuAl2 on the grain boundaries. In contrast, moderate Si addition inhibited IGC because the decrease of the Mn content in the grain interiors due to enhanced precipitation of Al15(Mn,Fe)3Si2 in the grain. Additionally, Cu-depleted zone also disappeared because preferential precipitation of CuAl2 on the grain boundaries was prevented. The excess-Si alloy exhibited high IGC susceptibility because Si-depleted zone formed around the grain boundaries as a result of the preferential precipitation of coarse Si particles on the grain boundaries although the Mn/Cu-depleted zones were not formed.
  • Hydrogenation of Propyne Verifying the Harmony in Surface and Bulk Compositions for Fe-Ni Alloy Nanoparticles

    pp. 776-781

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    DOI:10.2320/matertrans.MBW201606

    We investigated the catalytic properties of Fe1−xNix nanoparticles prepared by a polyol-based method that allowed the precise control of their composition and structure. In the hydrogenation of propyne, the reaction rate decreased with decreasing x, which was in good agreement with the scenario that inactive Fe atoms dilute active Ni ensembles in particles at 0.55 ≤ x ≤ 1. For particles with x ≤ 0.46, it was suggested that slightly active Fe-Ni ensembles mainly contributed to the activity due to small population of active Ni ensembles. Since the change in catalytic properties with x was well explained by the assumption that the surface composition corresponded to x, it was concluded that the surface composition dominating the catalytic properties can be tuned by adjusting the entire composition of nanoparticles.
  • The Application of Etched Aluminum Wires as Catalyst Supports for Methanol Steam-Reforming

    pp. 782-789

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    DOI:10.2320/matertrans.M2016454

    In the present work, we investigated the alternating current (AC) etching of aluminum wires with the aim of fabricating catalyst supports. This support material was found to possess a spongy surface layer that could be subsequently filled with γ-alumina by a combination of hydration and calcination. These support wires are easily fabricated at low cost, and could be mass produced continuously. The integrated structure of the catalyst produces a strong interconnection between the wire substrate and a thick catalyst layer on the wire. This work also demonstrated that the diffusion inside the catalyst layer can be controlled by varying the etched structure of the support layer. A micro-structured catalytic wall reactor concept was developed using these wires, situated parallel to one another within a tubular device, such that microchannels were present between the wires. The steam-reforming of methanol was assessed in this type of microreactor.
  • Effect of Sodium Carbonate on Phase Transformation of High-Magnesium Laterite Ore

    pp. 790-794

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    DOI:10.2320/matertrans.M2016439

    The phase transformation of high-magnesium laterite ore were investigated during the reduction roasting process. In the absence of sodium carbonate [Na2CO3], the X-ray diffraction results indicate that the [Fe Ni] alloy existed in ore in the form of taenite. The taenite particles is fine and the size is approximately 30–40 nm, which indicate that the nickel and iron are not migrated and aggregated during the non-smelting reduction roasting process. In the presence of sodium carbonate, the intensity of [Fe Ni] alloy phase increases; the taenite diffraction peaks disappears, corresponding to the appearance of kamacite. The results of SEM images show that the [Fe Ni] alloy particle size has a significant increase with the addition of Na2CO3. Based on the theoretical analysis, the pivotal role of Na2CO3 may be mainly attributed to the Na+, which could infiltrate into the crystal lattice of FeO, leading to the lattice distortion. Furthermore, the sodium carbonate would be decomposed at high temperature, and the generated CO2 could promote the Boudouard reaction which produced the CO to enhance the reduction of metallic oxides within ore.
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  • Electrocapillary Deformation and Electric Voltage Induced Flow of Liquid Wood Alloy in NaOH Aqueous Solution

    pp. 795-798

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    DOI:10.2320/matertrans.M2016414

    Electrocapillary behaviors for liquid Wood alloy in NaOH aqueous solution by applying external low voltage were investigated. The electrode reaction (redox reaction) induced the formation or removing of oxide film, and further caused the drop deformation by decreasing or increasing of interfacial tension. The same polar charge in the electric double layer would also decrease the interfacial tension. In order to maintain the stability of the system, the contact area of the interface would be expanded, and induced drop deformation macroscopically. When the liquid metal was charged by the chemical reaction in the solution, the electric field force is an effective way to drive it.
  • Thermal and Mechanical Properties of Commercial-Purity Aluminum Fabricated Using Selective Laser Melting

    pp. 799-805

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    DOI:10.2320/matertrans.L-M2017809

    Optimal laser scanning parameters to densify commercial-purity aluminum, fabricated using selective laser melting (SLM), were studied using an SLM machine equipped with a 400 W Yb fiber laser. The SLM samples with a relative density of 99.7% were obtained. The microstructures and the thermal and mechanical properties of the dense SLM samples fabricated using the optimal laser scanning parameters were investigated. The as-fabricated SLM samples had granular microstructures of aluminum, silicon, and/or iron oxides dispersed finely (~0.3 μm) due to the rapid solidification by laser irradiation. The mechanical properties were thus confirmed to be excellent (ultimate tensile strength: 110 MPa, proof stress: 90 MPa, breaking elongation: 30%). The thermal conductivity of the SLM sample was approximately 200 W/m·K, which was slightly inferior to that of the wrought commercial-purity aluminum (230 W/m·K). The effect of annealing on the properties of the SLM samples were also investigated. The thermal conductivity of the SLM sample annealed at 450℃ for 10 minutes increased to the same value as that of the wrought commercial-purity aluminum, although both the proof stress and breaking elongation were slightly decreased. This Paper was Originally Published in Japanese in J. JILM 66 (2016) 167–173.
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  • Deposition of DLC Films onto Oxynitriding-Treated V4E High Vanadium Tool Steel through DC-Pulsed PECVD Process

    pp. 806-812

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    DOI:10.2320/matertrans.M2016375

    In this work, DLC films are prepared by DC-pulsed PECVD after the oxynitriding treatment of V4E high vanadium tool steel. The experimental design includes various power densities (200, 400, 600 and 800 mW·cm−2) with an unbalanced bipolar-pulsed voltage. The deposition time is 90 min, and the CH4 gas flow is maintained at 5 sccm, respectively. The experimental results show the duplex coating layers to have better properties when the DLC films are treated by an appropriate power density (400 mW·cm−2). These films also possess the lowest wear loss volume (for loads of 2 N and 5 N of 6.23 × 10−3 mm3 and 1.19 × 10−2 mm3, respectively), the lowest corrosion current (4.09 × 10−4 A·cm−2) and the highest polarization resistance (258.83 Ω·cm2) after the 3.5 mass% NaCl corrosion test. This study confirms that the wear and corrosion resistance of V4E tool steel can be effectively improved through the DLC/oxynitriding duplex treatment.
  • Effect of Bias Sputtering on Magnetostrictive Property of Sm-Fe Thin Film

    pp. 813-816

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    DOI:10.2320/matertrans.MBW201610

    The Sm-Fe thin films were prepared by a DC magnetron sputtering system installed the Langmuir probe with various substrate bias voltage. In this work, internal stress of the Sm-Fe thin films was investigated considering ion bombardment. The influence of ion bombardment on internal stress in films was estimated by the ion bombardment parameter (Pi). The Pi increased with increasing negative substrate voltage. Internal stress of Sm-Fe thin films showed a larger compressive stress with increasing amount of the Pi. The magnetostrictive susceptibility of Sm-Fe thin films was improved by increasing compressive stress. The magnetostrictive susceptibility of the Sm-Fe thin film was dependent on the Pi.
  • Morphology Evolution of γ′ Precipitates during Isothermal Exposure in Wrought Ni-Based Superalloy Inconel X-750

    pp. 817-824

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    DOI:10.2320/matertrans.M2016376

    The morphological evolution of γ′ precipitates and lattice misfit with isothermal aging were closely investigated in wrought Ni-based superalloy Inconel X-750. The γ′ morphology dramatically changes in terms of shape, distribution, coalescence and coherency at the γ/γ′ interface. These processes and their dependence on temperature are summarized as a γ′ morphology map together with a time–temperature–precipitation (TTP) diagram through quantifying relevant morphological parameters. The lattice misfit was measured by X-ray diffraction and is positive; it decreases from 0.6% at room temperature to 0.1% at the aging temperature. These results suggest that the morphological changes of the γ′ precipitates are attributable to very low lattice misfit, the interaction of the elastic field, the volume fraction of the precipitates and incoherence in γ/γ′ interface.
  • Improvement of Coercivity of Nd-Fe-B Powder by Nd-Cu Sputtering

    pp. 825-828

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    DOI:10.2320/matertrans.M2016448

    This paper reports improvement of the coercivity of Nd-Fe-B powder by Nd-Cu sputtering. The total rare earth element content of the Nd-Fe-B powder increased by 0.8 mass% after Nd-Cu sputtering, and the sputtered Nd-Cu was observed at the surface of Nd-Fe-B powder by microstructural observation. The coercivity (Hc) of the Nd-Cu-sputtered Nd-Fe-B powder improved after annealing at temperatures above 600℃, and Hc of the sputtered powder reached a maximum value of 1312 kA m−1 after annealing at 900℃. This Hc value was 470 kA m−1 higher than that of Nd-Fe-B powder without sputtering. Isotropic green compacts were prepared from Nd-Fe-B powders with and without Nd-Cu sputtering, and the sputtering also improved Hc in the compacts. The compact prepared from powder with sputtering had Hc of 630 kA m−1 higher than that of the compact prepared from powder without sputtering after annealing at 900℃. Microstructure observation showed that the improvement of Hc was due to an increase in the Nd-rich phase in the compact by Nd-Cu sputtering.
  • Recovery of Silver from the Nitrate Leaching Solution of a Spent Ag/α-Al2O3 Catalyst by Solvent Extraction and Reduction

    pp. 829-833

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    DOI:10.2320/matertrans.M2017019

    Nitric acid was employed to strip silver from loaded 5,8-diethyl-7-hydroxy-dodecan-6-oxime (LIX63) in the recovery of silver from a leaching solution of a spent Ag/α-Al2O3 catalyst. The loaded LIX63 was obtained by contacting the real leaching solution with 0.5 mol/dm3 LIX63 diluted in kerosene. In order to produce silver powder by reduction, the HNO3 in the stripping solution was recovered by extraction with tri 2-ethylhexyl amine (TEHA) followed by stripping with distilled water. Silver powder was obtained by reduction with 0.1 mol/dm3 L-ascorbic acid. A flowsheet was proposed to recover Ag from the leaching solution of the spent Ag/α-Al2O3 catalyst by solvent extraction and reduction with minimum waste emissions.
  • Manufacturing of Carbon Nanotube Preform with High Porosity and Its Application in Metal Matrix Composites

    pp. 834-837

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    DOI:10.2320/matertrans.M2017018

    A new process is proposed to manufacture carbon nanotube preform and carbon nanotube (vapor grown carbon fiber, VGCF)-reinforced aluminum matrix composite. Carbon nanotube preform is fabricated using a mixtures of mesophase pitch (MP) and VGCF. The VGCF-MP-preform-reinforced aluminum composite was manufactured by a low-pressure casting method, with a pressure of 0.8 MPa. The effect of the addition ratio of MP powder and VGCF on VGCF-MP-preform was observed. Therefore, microstructure of VGCF-MP-preform-reinforced aluminum composites with and without nickel plating was observed.
  • EBSD Observation of Pure Iron with Near-Cube Orientation Fabricated by Cold Rolling and Annealing

    pp. 838-841

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    DOI:10.2320/matertrans.M2016443

    The orientation characteristics of a pure iron tape fabricated by cold rolling and annealing were evaluated using electron backscatter diffraction (EBSD) analysis. The {1 7 1}<4 3 17> orientation, which is a near-cube orientation, was strongly formed on the tape surface. For the oriented iron tape, the out-of-plane misorientation of (0 0 1) from the cube orientation is ca. 11°. The areal fraction of cube orientations with an angular deviation ≤20° amounts to 94.7%. The average grain size is approximately 370 μm for the near-cube oriented iron tape.
  • Properties and Morphologies of Epoxy Resin Based Composites Reinforced by Polyurethane and Graphene Oxide

    pp. 842-844

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    DOI:10.2320/matertrans.M2016464

    Graphene oxide/polyurethane/epoxy resin nanocomposites containing various contents of graphene oxide were prepared by a sequential physical and polymeric technique. For the nanocomposites with a 0.3 mass% loading of graphene oxide, great improvement in tensile properties such as the elongation at break and toughness have been achieved by 45% and 87%, respectively. Meanwhile, the damping property of the nanocomposites is superior to that of the polyurethane/epoxy composite, with a 1℃ loss for the glass transition temperature. Combined with the morphology analysis, it has been proved that the polyurethane prepolymer terminated with hydroxyl groups and graphene oxide exhibit synergistic effect on improving mechanical properties of neat epoxy resin.
  • Erratum

    pp. 845-845

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    DOI:10.2320/matertrans.ERM201702

Article Access Ranking

26 Jun. (Last 30 Days)

  1. Perspective toward Long-term Global Goal for Carbon Dioxide Mitigation in Steel Industry Tetsu-to-Hagané Vol.105(2019), No.6
  2. Hydrogen Embrittlement Susceptibility Evaluation of Tempered Martensitic Steels Showing Different Fracture Surface Morphologies ISIJ International Advance Publication
  3. Production and Technology of Iron and Steel in Japan during 2018 ISIJ International Vol.59(2019), No.6
  4. Effect of a Zn Interlayer on the Adhesion Strength and Corrosion Resistance of Zn–Mg Coated TRIP Steel ISIJ International Vol.59(2019), No.6
  5. A Kinetic Model of Mass Transfer and Chemical Reactions at a Steel/Slag Interface under Effect of Interfacial Tensions ISIJ International Vol.59(2019), No.5
  6. Fundamentals of Silico-Ferrite of Calcium and Aluminium (SFCA) Iron Ore Sinter Bonding Phase Formation: Effects of Titanium on Crystallisation during Cooling ISIJ International Vol.59(2019), No.6
  7. Evaluation of the Structure and Strength of Coke with HPC Binder under Various Preparation Conditions ISIJ International Advance Publication
  8. Recycling of Blast Furnace Sludge to the Blast Furnace via Cold-Bonded Briquettes: Evaluation of Feasibility and Influence on Operation ISIJ International Advance Publication
  9. Improvement of Sinter Strength and Reducibility through Promotion of Magnetite Ore Oxidation by Use of Separate Granulating Method ISIJ International Vol.59(2019), No.5
  10. Effects of Surface Microstructure on Selective Oxidation Morphology and Kinetics in N2 + 5%H2 Atmosphere with Variable Dew Point Temperature ISIJ International Vol.59(2019), No.5

Search Phrase Ranking

26 Jun. (Last 30 Days)

  1. blast furnace
  2. blast furnace permeability
  3. blast furnace productivity
  4. assimilation
  5. bubbling ladle
  6. inclusions
  7. isij xafs
  8. lme
  9. phosphatability
  10. phosphate treatment