scholarly journals The Effect of External Magnetic Field on Microstructure and Magnetic Properties of Melt-Spun Nd-Fe-B/Fe-Co Nanocomposite Ribbons

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Xuan Truong Nguyen ◽  
Hong Ky Vu ◽  
Hung Manh Do ◽  
Van Khanh Nguyen ◽  
Van Vuong Nguyen
Keyword(s):  
Magnetic Field ◽  
Grain Size ◽  
High Performance ◽  
Melt Spinning ◽  
Nominal Composition ◽  
Energy Product ◽  
Melt Spun ◽  
Spinning Process ◽  
Reduction Effect ◽  
Microstructure And Magnetic Properties

The ribbons Nd2Fe14B/Fe-Co were prepared with the nominal composition Nd16Fe76B8/40% wt. Fe65Co35by the conventional and the developed magnetic field-assisted melt-spinning (MFMS) techniques. Both ribbons are nanocomposites with the smooth single-phase-like magnetization loops. The 0.32 T magnetic field perpendicular to the wheel surface and assisting the melt-spinning process reduces the grain size inside the ribbon, increases the texture of the ribbon, improves the exchange coupling, and, in sequence, increases the energy product(BH)maxof the isotropic powdered samples of MFMS ribbon in ~9% by comparison with that of the ribbon melt-spun conventionally. The grain size reduction effect caused by the assisted magnetic field has also been described quantitatively. The MFMS technique seems to be promising for producing high-performance nanocomposite ribbons.

scholarly journals Magnetic field assisted melt–spinning Nd-Fe-B ribbons and anisotropic bonded NdFeB magnets prepared thereof

2016 ◽  
Vol 26 (1) ◽  
pp. 59
Author(s):  
Nguyen Xuan Truong ◽  
Nguyen Van Vuong
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
High Temperature ◽  
Melt Spinning ◽  
Milling Process ◽  
Mixed Powder ◽  
Energy Product ◽  
Hot Compaction ◽  
The Magnetic Field ◽  
Microstructure And Magnetic Properties

The magnetic-field-assisted melt-spinning (FAMS) Nd10.5Fe72Co11B6.5 ribbons were spun in an external magnetic field of 3 kG. The prepared ribbons were ball-milled in xylene solvent for 30 minutes followed by adding in and mixing with the high-temperature binder HTB-1 (3 wt%) for further 10 minutes. The mixed powder was dried and in-mold aligned in a magnetic field of 18 kOe and hot-compacted at 200 oC. The parameters of the FAMS ribbon preparation, ball-milling process, hot-compaction and anisotropic bonded magnets’ fabrication were optimized leading to the magnet’s energy product (BH)max of 10 MGOe. The microstructure and magnetic properties of prepared ribbons and bonded magnets will be discussed in details.

scholarly journals Phase Formation, Microstructure, and Magnetic Properties of Nd14.5Fe79.3B6.2 Melt-Spun Ribbons with Different Ce and Y Substitutions

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3992
Author(s):  
Qingjin Ke ◽  
Feilong Dai ◽  
Shengxi Li ◽  
Maohua Rong ◽  
Qingrong Yao ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Phase Formation ◽  
High Performance ◽  
Magnetic Energy ◽  
Co Substitution ◽  
Energy Product ◽  
Melt Spun ◽  
Low Costs ◽  
Melt Spun Ribbons ◽  
Microstructure And Magnetic Properties

Phase formation and microstructure of (Nd1-2xCexYx)14.5Fe79.3B6.2 (x = 0.05, 0.10, 0.15, 0.20, 0.25) alloys were studied experimentally. The results reveal that (Nd1-2xCexYx)14.5Fe79.3B6.2 annealed alloys show (NdCeY)2Fe14B phase with the tetragonal Nd2Fe14B-typed structure (space group P42/mnm) and rich-RE (α-Nd) phase, while (Nd1-2xCexYx)14.5Fe79.3B6.2 ribbons prepared by melt-spun technology are composed of (NdCeY)2Fe14B phase, α-Nd phase and α-Fe phase, except for the ribbon with x = 0.25, which consists of additional CeFe2 phase. On the other hand, magnetic properties of (Nd1-2xCexYx)14.5Fe79.3B6.2 melt-spun ribbons were measured by a vibrating sample magnetometer (VSM). The measured results show that the remanence (Br) and the coercivity (Hcj) of the melt-spun ribbons decrease with the increase of Ce and Y substitutions, while the maximum magnetic energy product ((BH)max) of the ribbons decreases and then increases. The tendency of magnetic properties of the ribbons could result from the co-substitution of Ce and Y for Nd in Nd2Fe14B phase and different phase constitutions. It was found that the Hcj of the ribbon with x = 0.20 is relatively high to be 9.01 kOe, while the (BH)max of the ribbon with x = 0.25 still reaches to be 9.06 MGOe. It suggests that magnetic properties of Nd-Fe-B ribbons with Ce and Y co-substitution could be tunable through alloy composition and phase formation to fabricate novel Nd-Fe-B magnets with low costs and high performance.

Microstructure Analysis of Melt-Spun Al3Ti Intermetallics by XRD and EXAFS

1996 ◽  
Vol 460 ◽  
Author(s):  
Jinmin Chen ◽  
W. E. Frazier ◽  
E. V. Barrera
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Melt Spinning ◽  
Composition Range ◽  
Processing Parameters ◽  
Wheel Speed ◽  
Annealing Temperatures ◽  
Melt Spun ◽  
Temperature Heat ◽  
Spinning Process

ABSTRACTIn an effort to expand the composition range over which Al3Ti is stable, various amounts of niobium were substituted for titanium and processed by melt-spinning. Several samples were annealed both at 600°C and 1000°C for 24 hours. The effects of processing parameters such as wheel speed, the amount of niobium, and annealing temperatures on the structure were investigated by XRD and EXAFS. XRD showed that for all the samples the only structure present was DO22-The DO22 structure was stable even after the high temperature heat treatments. By means of EXAFS, niobium atoms were observed to occupy titanium sites in the DO22 structure. Furthermore, in the unannealed samples, increasing wheel speed of the melt spinning process or the niobium concentration tended to distort the crystal structure. It was observed that Ti EXAFS had different results from the Nb EXAFS beyond their occupying similar sites, which suggested there may exist some composition zones, i.e. rich Nb zone or rich Ti zones, although the structures present were still DO22. The samples were found to experience different distortions as a function of annealing temperatures.

Optimization of Manufacturing Parameters for Melt Spun Yarns Using Taguchi Method

2014 ◽  
Vol 556-562 ◽  
pp. 4264-4267
Author(s):  
Shu Wen Wang ◽  
Te Li Su
Keyword(s):  
Taguchi Method ◽  
Melt Spinning ◽  
Parameter Design ◽  
Controllable Factors ◽  
Melt Spun ◽  
Spun Yarns ◽  
Spinning Process ◽  
Polypropylene Melt ◽  
Manufacturing Parameters

In melt spinning process, evenness of polypropylene melt spun yarns affects the appearance, hairiness, strength and productivity of yarns, as well as product production and profits, causing rejection due to nonconformity. The research is to find optimal manufacturing parameters of melt spun yarns. Firstly, to proceed the parameter design by Taguchi method, then to select a manufacturing parameter which will affect the quality of melt spun yarns as controllable factors. Also to choose a suitable orthogonal arrays. Meanwhile, according to variation of analysis, to decide optimal manufacturing parameters of melt spun yarns and its remarkable factor. Finally, using 95% confidence interval to proof the experiment’s reliability and repeatability.

Effect of Dysprosium Content on the Magnetic Properties of Nanocrystalline (Pr0.25Nd0.75)10-xDyxFe82Co2B6 Alloys

2014 ◽  
Vol 789 ◽  
pp. 28-31 ◽  
Author(s):  
He Wei Ding ◽  
Chun Xiang Cui ◽  
Ji Bing Sun
Keyword(s):  
Magnetic Properties ◽  
Melt Spinning ◽  
Maximum Energy ◽  
Vibrating Sample Magnetometer ◽  
X Ray ◽  
Maximum Energy Product ◽  
Energy Product ◽  
Intrinsic Coercivity ◽  
Electronic Microscope ◽  
Microstructure And Magnetic Properties

(Pr0.25Nd0.75)10-xDyxFe82Co2B6(x=0~0.3) ribbons were prepared by melt spinning at 25m/s and subsequent annealing. The effect of Dy content on the microstructure and magnetic properties of the ribbons has been investigated by X-ray diffractometer (XRD), scanning electronic microscope (SEM) and vibrating sample magnetometer (VSM). The magnetic properties related to the Dy content were characterized. Intrinsic coercivity of 598kA/m, remanence of 0.58T, and the maximum energy product (BH)max of 43kJ/m3 were achieved in (Pr0.25Nd0.75)9.8Dy0.2Fe82Co2B6 after annealing at 700°C for 10 minutes.

Effect of Rapid Quenching in Magnetic Field on the Microstructures and Electrochemical Performances of AB5-Type Alloys

2012 ◽  
Vol 512-515 ◽  
pp. 1589-1596
Author(s):  
You Gen Tang ◽  
Chen Xi Jiang ◽  
Ya Zhi Wang ◽  
Xiao Pei Gao ◽  
Jin Bao Zhang
Keyword(s):  
Magnetic Field ◽  
Grain Size ◽  
Melt Spinning ◽  
Rapid Quenching ◽  
Electrochemical Performances ◽  
Electrochemical Studies ◽  
Cycle Stability ◽  
Oriented Growth ◽  
Cell Parameters ◽  
Diffusion Of Hydrogen

Direct magnetic field was imposed during the process of rapid quenching by melt spinning of MlNi3.6Co0.7Mn0.4Al0.3 and MlNi3.6Co0.35Mn0.5Al0.3Cu0.25. The effect of rapid quenching in magnetic field on the microstructures and electrochemical performances was investigated in detail. The results show that rapid quenching decreases the grain size of both alloys, and magnetic field results in an oriented growth especially for MlNi3.6Co0.35Mn0.5Al0.3Cu0.25 alloys, but they have little influence on the typical CaCu5 structure of AB5-type alloys except for the increase of cell parameters (a0, c0) and cell volume. Electrochemical studies indicate that rapid quenching enhances the cycle stability significantly but inevitably decreases the electrochemical capacities of the alloys unless magnetic field was imposed. Additionally, the diffusion of hydrogen and rate properties are improved with the emergence of magnetic field compared with the alloys processed by rapid quenching only.

Reliable Sn–Ag–Cu lead-free melt-spun material required for high-performance applications

2019 ◽  
Vol 234 (11-12) ◽  
pp. 757-767 ◽  
Author(s):  
Mohammed Mundher Jubair ◽  
Mohammed S. Gumaan ◽  
Rizk Mostafa Shalaby
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Electrical Resistivity ◽  
High Performance ◽  
Melt Spinning ◽  
High Strength ◽  
Thermal Environments ◽  
Aerospace Applications ◽  
Melt Spun ◽  
Melt Spinning Technique

AbstractThis study investigates the structural, mechanical, thermal and electrical properties of B-1 JINHU, EDSYN SAC5250, and S.S.M-1 commercial materials, which have been manufactured at China, Malaysia, and Germany, respectively. The commercial materials have been compared with the measurements of Sn–Ag–Cu (SAC) melt-spun materials that are only indicative of what can be expected for the solder application, where the solder will have quite different properties from the melt-spun materials due to the effects of melt-spinning technique. Adding Cu to the eutectic Sn–Ag melt-spun material with 0.3 wt.% significantly improves its electrical and mechanical properties to serve efficiently under high strain rate applications. The formed Cu3Sn Intermetallic compound (IMC) offers potential benefits, like high strength, good plasticity, consequently, high performance through a lack of dislocations and microvoids. The results showed that adding 0.3 wt.% of Cu has improved the creep resistance and delayed the fracture point, comparing with other additions and commercial solders. The tensile results showed some improvements in 39.3% tensile strength (25.419 MPa), 376% toughness (7737.220 J/m3), 254% electrical resistivity (1.849 × 10−7 Ω · m) and 255% thermal conductivity (39.911 w · m−1 · k−1) when compared with the tensile strength (18.24 MPa), toughness (1625.340 J/m3), electrical resistivity (6.56 × 10−7 Ω · m) and thermal conductivity (11.250 w · m−1 · k−1) of EDSYN SAC5250 material. On the other hand, the Sn93.5–Ag3.5–Cu3 melt-spun solder works well under the harsh thermal environments such as the circuits located under the automobiles’ hood and aerospace applications. Thus, it can be concluded that the melt-spinning technique can produce SAC melt-spun materials that can outperform the B-1 JINHU, EDSYN SAC5250 and S.S.M-1 materials mechanically, thermally and electrically.

Theory and Simulation of Fiber Texture Formation and Rheology of Carbonaceous Mesophase Fibers

2001 ◽  
Vol 709 ◽  
Author(s):  
A. D. Rey
Keyword(s):  
Liquid Crystals ◽  
High Performance ◽  
Melt Spinning ◽  
Elongational Flow ◽  
Fiber Texture ◽  
Texture Formation ◽  
Cross Sectional ◽  
Wide Range ◽  
Spinning Process ◽  
Sectional Shape

ABSTRACTCarbonaceous mesophases are discotic nematic liquid crystals that are spun into high performance carbon fibers using the melt spinning process. The spinning process produces a wide range of different fiber textures and cross-sectional shapes. Circular planar polar (PP), circular planar radial (PR) textures, ribbon planar radial (RPR), and ribbon planar line (RPL) textures are ubiquitous ones. This paper presents, solves, and validates a model of mesophase fiber texture formation based on the classical Landau-de Gennes theory of liquid crystals, adapted here to carbonaceous mesophases. The effects of fiber cross-sectional shape and elongational flow on texture formation are characterized. Emphasis is on qualitative model validation using existing experimental data [1, 2]. The results provide additional knowledge on how to optimize and control mesophase fiber textures.

scholarly journals Microstructure Evolution and Mechanical Properties of Melt Spun Skutterudite-based Thermoelectric Materials

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 984 ◽  
Author(s):  
Huiyuan Geng ◽  
Jialun Zhang ◽  
Tianhong He ◽  
Lixia Zhang ◽  
Jicai Feng
Keyword(s):  
Mechanical Properties ◽  
Spinodal Decomposition ◽  
Microstructure Evolution ◽  
Thermoelectric Materials ◽  
High Performance ◽  
Melt Spinning ◽  
Bending Strength ◽  
Annealed Sample ◽  
Submicron Scale ◽  
Spinning Process

The rapid solidification of melt spinning has been widely used in the fabrication of high-performance skutterudite thermoelectric materials. However, the microstructure formation mechanism of the spun ribbon and its effects on the mechanical properties are still unclear. Here, we report the microstructure evolution and mechanical properties of La–Fe–Co–Sb skutterudite alloys fabricated by both long-term annealing and melt-spinning, followed by sintering approaches. It was found that the skutterudite phase nucleated directly from the under-cooled melt and grew into submicron dendrites during the melt-spinning process. Upon heating, the spun ribbons started to form nanoscale La-rich and La-poor skutterudite phases through spinodal decomposition at temperatures as low as 473 K. The coexistence of the micron-scale grain size, the submicron-scale dendrite segregation and the nanoscale spinodal decomposition leads to high thermoelectric performance and mechanical strength. The maximum three-point bending strength of the melt spinning sample was about 195 MPa, which was 70% higher than that of the annealed sample.

Sign in / Sign up

Export Citation Format

Share Document