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T. Masumoto - One of the best experts on this subject based on the ideXlab platform.
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Soft-Magnetic Properties of Nanocrystalline Fe-Zr-B-Ni Bulk Alloy Produced by Warm Extrusion
Japanese Journal of Applied Physics, 2014Co-Authors: Akinori Kojima, Akihiro Makino, Y. Kawamura, Akihisa Inoue, T. MasumotoAbstract:Magnetic properties of nanocrystalline Fe90-x Zr7B3Nix ( x=2–4) melt-spun ribbons and consolidated Bulk Alloys have been investigated. The magnetostriction of Fe90-x Zr7B3Nix ribbon changed from -1.8×10-6 to 1.8×10-6 when x changed from 0 to 4 and became zero at x=1.5. Soft-magnetic properties of ribbon and consolidated Bulk Fe90-x Zr7B3Nix were better than those of Fe90Zr7B3. Nanocrystalline Fe86Zr7B3Ni4 consolidated Bulk with grain sizes of 10–20 nm exhibited magnetic flux density of 1.55 T, maximum permeability of 23000, effective permeability of 3360 at 300 Hz, and coercivity of 14 A/m.
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Soft-magnetic properties of nanocrystalline bcc Fe-(Nb, Zr)-B Bulk Alloys consolidated by warm extrusion
Materials Transactions Jim, 1995Co-Authors: Akinori Kojima, Akihiro Makino, H. Horikiri, Y. Kawamura, Akihisa Inoue, T. MasumotoAbstract:We obtained Fe 84 Nb 7 B 9 Bulk Alloys by extruding amorphous powders at temperatures (T e ) between 653 and 723 K and pressures (P e ) of 820 to 1210 MPa, and Fe 90 Zr 7 B 3 Bulk Alloys by extruding at T e of 673 to 698 K and P e of 920 to 940 MPa. Subsequent annealing of these Bulk Alloys at 923 K for 3.6 ks causes the formation of a nanocrystalline bcc phase with grain sizes of 9 to 11 nm for Fe 84 Nb 7 B 9 and 20 to 30 nm for Fe 90 Zr 7 B 3 . The bcc Fe 84 Nb 7 B 9 Bulk Alloy exhibits a magnetization (B 800 ) of 1.40 T, a permeability (μ e ) of 1120 at 300 Hz, and a coercive force (H c ) of 48 A/m in the extrusion condition of T e =698 K and P e =870 MPa. Similarly, the B 800 , μ e and H c of the bcc Fe 90 Zr 7 B 3 Bulk Alloy prepared at T e =698 K and P e =923 MPa are 1.57T, 1880 and 29A/m, respectively. The soft-magnetic properties of the bcc Fe 90 Zr 7 B 3 Bulk Alloy are superior to those of the bcc Fe 84 Nb 7 B 9 Bulk Alloy, presumably because of the formation of a more homogeneous bcc structure for the former Alloy.
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Production of nanocrystalline b.c.c. FeNbB Bulk Alloys by warm extrusion and their magnetic properties
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1994Co-Authors: Akinori Kojima, Akihiro Makino, H. Horikiri, Y. Kawamura, Akihisa Inoue, T. MasumotoAbstract:Abstract A Bulky Fe 84 Nb 7 B 9 Alloy was obtained by extruding the powders ground from amorphous ribbon, at temperatures T e between 563 K and 723 K at pressures P e between 824 MPa and 1208 MPa and at a speed of 5 mm s −1 . The Bulk Fe 84 Nb 7 B 9 Alloy extruded at T e = 698 K and P e = 1208 MPa is in a fully consolidated state has a density of about 99%. The Bulk Alloy is composed of a mostly single b.c.c. phase with a grain size of about 10 nm after annealing for 3.6 ks at temperatures between 873 K and 973 K, and its soft magnetic property tends to better for the Bulks extruded at lower pressures. The Bulk Alloy extruded at T e = 698 K and P e = 824 MPa exhibits a high saturation magnetization B s of 1.40 T and a low coercive force H c of 64 A m −1 after annealing at 698 K.
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Magnetic Properties of Extruded Nanocrystalline Fe-Nb-B Alloys
IEEE Translation Journal on Magnetics in Japan, 1994Co-Authors: A. Kojima, A. Inoue, H. Horikiri, Y. Kawamura, A. Makino, T. MasumotoAbstract:A Bulk Fe84Nb7B9 Alloy was produced by extruding amorphous powder at temperatures (Te) between 653 and 723K, at pressures (Pe) between 824 and 1208 MPa, and at a speed (Ve) of 5 mm/s. The subsequent annealing of the extruded Bulk Alloy for 3.6 ks at temperatures between 873 and 973K resulted in the formation of a (for the most part) single bec phase, with grain sizes near 10 nm. The Bulk Alloy, extruded at a Pe above 1000 MPa, has a high relative density of 99%. The soft magnetic properties are better for Bulk materials extruded at lower pressures, and the Bulk Alloy extruded at Te=698K and Pe=870 MPa exhibits a magnetization (B800) of 1.40 T, a permeability of 1123, and a coercive force (Hc) of 47 A/m, values which are inferior to those of the bec ribbon Alloy (1.49 T, 22000, 8 A/m). The difference between the soft magnetic properties of the Bulk material and the ribbon forms is presumably due to the inhomogeneity of the microstructure, oxidation of the powder, and the remainder of a higher internal stress in the Bulk Alloy.
Akinori Kojima - One of the best experts on this subject based on the ideXlab platform.
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Soft-Magnetic Properties of Nanocrystalline Fe-Zr-B-Ni Bulk Alloy Produced by Warm Extrusion
Japanese Journal of Applied Physics, 2014Co-Authors: Akinori Kojima, Akihiro Makino, Y. Kawamura, Akihisa Inoue, T. MasumotoAbstract:Magnetic properties of nanocrystalline Fe90-x Zr7B3Nix ( x=2–4) melt-spun ribbons and consolidated Bulk Alloys have been investigated. The magnetostriction of Fe90-x Zr7B3Nix ribbon changed from -1.8×10-6 to 1.8×10-6 when x changed from 0 to 4 and became zero at x=1.5. Soft-magnetic properties of ribbon and consolidated Bulk Fe90-x Zr7B3Nix were better than those of Fe90Zr7B3. Nanocrystalline Fe86Zr7B3Ni4 consolidated Bulk with grain sizes of 10–20 nm exhibited magnetic flux density of 1.55 T, maximum permeability of 23000, effective permeability of 3360 at 300 Hz, and coercivity of 14 A/m.
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Structural and magnetic properties of nanocrystalline fe-rich fe-nb-nd-b sintered magnets produced by consolidating amorphous powders
IEEE Transactions on Magnetics, 1997Co-Authors: Akinori Kojima, Akihiro Makino, A. InoueAbstract:Nanocrystalline Bulk Fe88Nb2Nd5B5and Fe86Nb2Nd7B5 Alloys were made by consolidating amorphous powders with an electric-pulse-currentsintering method and subsequent annealing. Bulk Alloy made by consolidating amorphous powders has a higher density (the maximum density could reach 7.5 g/cm3consolidating at 873 K and 636 MPa) than that made by consolidating crystalline powders, presumably because the amorphous Alloy softens around the crystallization temperature. The structure formed after annealing at 1023 K for 180 s shows a nanocrys talline composite consisting of bcc-Fe, Nd2Fe14B and Fe3B or Fe2B phases with grain sizes of 20-40 nm The nanocrystalline Bulk Fe88Nb2Nd5B5Alloy shows hard magnetic properties, remanence (Jr) of 1.05 T, coercive force (H0J) of 263 kA/m, and maximum energy product ((BH)max) of 75 kJ/m3. © 1997 IEEE.
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Soft-magnetic properties of nanocrystalline bcc Fe-(Nb, Zr)-B Bulk Alloys consolidated by warm extrusion
Materials Transactions Jim, 1995Co-Authors: Akinori Kojima, Akihiro Makino, H. Horikiri, Y. Kawamura, Akihisa Inoue, T. MasumotoAbstract:We obtained Fe 84 Nb 7 B 9 Bulk Alloys by extruding amorphous powders at temperatures (T e ) between 653 and 723 K and pressures (P e ) of 820 to 1210 MPa, and Fe 90 Zr 7 B 3 Bulk Alloys by extruding at T e of 673 to 698 K and P e of 920 to 940 MPa. Subsequent annealing of these Bulk Alloys at 923 K for 3.6 ks causes the formation of a nanocrystalline bcc phase with grain sizes of 9 to 11 nm for Fe 84 Nb 7 B 9 and 20 to 30 nm for Fe 90 Zr 7 B 3 . The bcc Fe 84 Nb 7 B 9 Bulk Alloy exhibits a magnetization (B 800 ) of 1.40 T, a permeability (μ e ) of 1120 at 300 Hz, and a coercive force (H c ) of 48 A/m in the extrusion condition of T e =698 K and P e =870 MPa. Similarly, the B 800 , μ e and H c of the bcc Fe 90 Zr 7 B 3 Bulk Alloy prepared at T e =698 K and P e =923 MPa are 1.57T, 1880 and 29A/m, respectively. The soft-magnetic properties of the bcc Fe 90 Zr 7 B 3 Bulk Alloy are superior to those of the bcc Fe 84 Nb 7 B 9 Bulk Alloy, presumably because of the formation of a more homogeneous bcc structure for the former Alloy.
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Production of nanocrystalline b.c.c. FeNbB Bulk Alloys by warm extrusion and their magnetic properties
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1994Co-Authors: Akinori Kojima, Akihiro Makino, H. Horikiri, Y. Kawamura, Akihisa Inoue, T. MasumotoAbstract:Abstract A Bulky Fe 84 Nb 7 B 9 Alloy was obtained by extruding the powders ground from amorphous ribbon, at temperatures T e between 563 K and 723 K at pressures P e between 824 MPa and 1208 MPa and at a speed of 5 mm s −1 . The Bulk Fe 84 Nb 7 B 9 Alloy extruded at T e = 698 K and P e = 1208 MPa is in a fully consolidated state has a density of about 99%. The Bulk Alloy is composed of a mostly single b.c.c. phase with a grain size of about 10 nm after annealing for 3.6 ks at temperatures between 873 K and 973 K, and its soft magnetic property tends to better for the Bulks extruded at lower pressures. The Bulk Alloy extruded at T e = 698 K and P e = 824 MPa exhibits a high saturation magnetization B s of 1.40 T and a low coercive force H c of 64 A m −1 after annealing at 698 K.
H. Yasuda - One of the best experts on this subject based on the ideXlab platform.
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Real time X-ray imaging of soldering processes at the SPring-8 synchrotron
2017 International Conference on Electronics Packaging (ICEP), 2017Co-Authors: K. Nogita, M.a.a. Mohd Salleh, G. Zeng, S.d. Mcdonald, C. Gourlay, H. YasudaAbstract:Real time X-ray imaging videos of the entire soldering process for preform solders, solder pastes and BGA solders as well as solder Alloy solidification and microstructure characterisation has been achieved over numerous experiments at the SPring-8 synchrotron. This paper overviews the developments of this challenging technique and provides key findings related to understanding the reliability of solder joints. There are large difference when comparing the microstructures and solidification pathways between soldered Alloys on Cu substrates (Cu-OSP) and Bulk Alloy solidification.
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Alloy phase formation in nanometer-sized particles
Materials Science and Engineering A, 2001Co-Authors: H Mori, H. YasudaAbstract:Alloy phase formation in nanometer-sized particles has been studied by transmission electron microscopy using particles in the Au-Sn system. When tin atoms are vapor-deposited onto nanometer-sized gold particles, rapid dissolution of tin atoms into gold particles takes place, and as a result, particles of an Au-rich solid solution, of a topologically disordered amorphous-like Alloy and of the AuSn compound are formed, depending upon the concentration of tin in a composition range from 0 to 59 at.% Sn. A remarkable enhancement of solubility has been observed in the Au-rich solid solution and the AuSn compound. There is a possibility that the topologically disordered amorphous-like phase, which appears in the middle of a two-phase region (i.e. Au5Sn-AuSn region) of the phase diagram for the Bulk Alloy, is not a non-equilibrium phase. © 2001 Elsevier Science B.V. All rights reserved.
J A Rejent - One of the best experts on this subject based on the ideXlab platform.
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intermetallic compound layer development during the solid state thermal aging of 63sn 37pb solder au pt pd thick film couples
IEEE Transactions on Components Packaging and Manufacturing Technology: Part A, 1997Co-Authors: Paul T Vianco, J J Stephens, J A RejentAbstract:A study was performed which examined the solid state, intermetallic compound layer growth kinetics between 63Sn-37Pb solder and a 76Au-21Pt-3Pd (wt.%) thick film conductor on 96% alumina substrates. A linear, multivariable regression analysis was used to assess the experimental data according to the following empirical relationship: x-x0=At/sup n/ exp(-/spl Delta/H/RT). A time exponent of n=0.78/spl plusmn/0.08 was observed, suggesting that a combination of Bulk diffusion and interface reaction mechanisms were responsible for layer growth. The apparent activation energy, /spl Delta/H, was 106/spl ges/8 kJ/mol. Parallel aging experiments were performed on diffusion couples fabricated between 63Sn-37Pb solder and Bulk Alloy stock having the same Au-Pt-Pd composition as the thick film. Similar growth kinetic parameters were computed. Intermetallic compound layer growth was accelerated under thermal cycling and thermal shock conditions due to residual stresses generated by the thermal expansion mismatch between the solder and the ceramic substrate.
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Intermetallic compound layer development during the solid state thermal aging of 63Sn-37Pb solder/Au-Pt-Pd thick film couples
IEEE Transactions on Components Packaging and Manufacturing Technology: Part A, 1997Co-Authors: Paul T Vianco, J J Stephens, J A RejentAbstract:A study was performed which examined the solid state, intermetallic compound layer growth kinetics between 63Sn-37Pb solder and a 76Au-21Pt-3Pd (wt.%) thick film conductor on 96% alumina substrates. A linear, multivariable regression analysis was used to assess the experimental data according to the following empirical relationship: x-x0=At/sup n/ exp(-/spl Delta/H/RT). A time exponent of n=0.78/spl plusmn/0.08 was observed, suggesting that a combination of Bulk diffusion and interface reaction mechanisms were responsible for layer growth. The apparent activation energy, /spl Delta/H, was 106/spl ges/8 kJ/mol. Parallel aging experiments were performed on diffusion couples fabricated between 63Sn-37Pb solder and Bulk Alloy stock having the same Au-Pt-Pd composition as the thick film. Similar growth kinetic parameters were computed. Intermetallic compound layer growth was accelerated under thermal cycling and thermal shock conditions due to residual stresses generated by the thermal expansion mismatch between the solder and the ceramic substrate.
Yuanyuan Li - One of the best experts on this subject based on the ideXlab platform.
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Microstructure and Mechanical Properties of SPSed (Spark Plasma Sintered) Ti66Nb13Cu8Ni6:8Al6:2 Bulk Alloys with and without WC Addition
Materials Transactions, 2009Co-Authors: Xiaoqiang Li, Chao Yang, Weiping Chen, Shengguan Qu, Yuanyuan LiAbstract:Ti66Nb13Cu8Ni6:8Al6:2 Bulk Alloys with and without WC addition were fabricated by spark plasma sintering and crystallization of amorphous phase. Microstructure analysis indicates that Ti66Nb13Cu8Ni6:8Al6:2 Bulk Alloy without WC addition has a ultrafine-grained microstructure with in situ precipitated ductile � -Ti(Nb) phase, composed of soft (Cu, Ni)-Ti2 regions surrounded by hard � -Ti regions. The Alloy exhibits high fracture strength of above 2000 MPa and remarkable plasticity of � 21%. In contrast, Ti66Nb13Cu8Ni6:8Al6:2 Bulk Alloys with WC addition consist of a microstructure of in situ precipitated ductile � -Ti regions surrounded by a mixed phase regions of (Cu, Ni)-Ti2, TiC, WC and residual glassy phase. The Alloys with WC addition display brittle facture behavior. The different plastic deformability for the fabricated Bulk Alloys with and without WC addition can be explained based on their distinctive microstructures. [doi:10.2320/matertrans.MF200924]
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vertically aligned 1d zno nanostructures on Bulk Alloy substrates direct solution synthesis photoluminescence and field emission
Journal of Physical Chemistry C, 2007Co-Authors: Xintang Huang, Yuanyuan Li, Xiaoxu Ji, Zikun Li, Xiang HeAbstract:We report a highly effective growth of vertically aligned ZnO one-dimensional (1D) nanostructures on conducting Alloy substrate (Fe−Co−Ni) in mild solutions (T ≤ 70 °C) in the absence of any seeds, catalysts, and surfactants. The growth conditions such as NH3·H2O concentration, temperature, and nature of the substrate are correlated to affect the nanostructure formation. Different ZnO single-crystal nanostructures including nanoneedles, hexagonal nanorods, and nanopencils oriented normal to the substrate can be selectively formed in high quantity. The ordered ZnO nanostructures show strong UV excitonic emissions and good field emission (FE) properties. Other metal substrates such as Ti and Ni are also proven to be effective for ZnO nanoarray growth. Since metal substrates are much more economical and scalable than Si, sapphire/Al2O3, GaN, etc., we believe that our approach presents a general economical route toward mass production of controllable ZnO arrays and will facilitate flexible design of device ar...
