Magnetic and Martensitic Transformations in Ni46Mn41.5-xFexSn12.5 Melt Spun Ribbons

Four alloys with nominal compositions Ni46Mn41.5-xFexSn12.5 (x=0, 2, 4, 6 at.%) were cast in an induction vacuum furnace and homogenized. Then they were melted in quartz tubes and ejected onto a rotating copper wheel to produce ribbons. The X-Ray phase analyses of as melt spun ribbons have shown that in both, the ternary as well as in the quaternary alloys a single phase of the Heusler L21 type ordered structure was found. The characteristic temperatures of magnetic (TC) and martensitic (Ms) transformations were determined by a vibrating sample magnetometer (VSM). Both the Ms and TC increase with the increase of Fe content in all alloys, which is in accordance with the theory of valence electron concentration (e/a) influence on Ms. The phase structures, chemical compositions, grains sizes and type of microsegregation were characterized by transmission electron microscope (TEM). The equi-axed grains of size from 0.95 to 1.7 μm were observed in all ribbons. The grains posses the L21 structure at room temperature, however in the alloys with higher Fe content the different type of martensite was observed at the grain boundaries of L21 phase. Appearance of this martensite was explained in relation to microsegregation of particular elements during melt spinning process and simultaneous change in the e/a ratio.

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SEM and TEM Studies of Magnetic Shape Memory NiCoMnIn Melt Spun Ribbons

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.186.251 ◽

2012 ◽

Vol 186 ◽

pp. 251-254 ◽

Cited By ~ 15

Author(s):

Wojciech Maziarz

Keyword(s):

Electron Microscopy ◽

Martensitic Transformations ◽

Crystallographic Structure ◽

Valence Electron Concentration ◽

Magnetic Shape Memory ◽

Two Phase ◽

Transmission Electron ◽

Melt Spun ◽

Columnar Grains ◽

Melt Spun Ribbons

Microstructure of Ni50-xCoxMn35.5In14.5 (x=0, 3, 5) melt-spun ribbons was investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The typical layered microstructure consisting of oriented columnar grains and colonies of fine equi-axed grains was observed in the cross section of ribbons. The crystallographic structure of ribbons varied with the content of Co in alloys what affected of their Ms temperature. For the x=0 the single phase of monoclinic 14M modulated martensite was observed, but for x=3 and 5, a two phase structure of L21 austenite and monoclinic 14M or orthorhombic 10M modulated martensite were identified. Different temperature range of martensitic transformations were explained basing on valence electron concentration per atom e/a versus Ms relationship.

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Microstructure of the Fe-Ni-P Melt-Spun Ribbons Produced from the Single-Chamber and from the Double-Chamber Crucibles

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.203-204.361 ◽

2013 ◽

Vol 203-204 ◽

pp. 361-367 ◽

Cited By ~ 5

Author(s):

Krzysztof Ziewiec ◽

Krystian Prusik ◽

Krzysztof Bryła ◽

Aneta Ziewiec

Keyword(s):

Electron Microscope ◽

Melt Spinning ◽

Melting Furnace ◽

Single Chamber ◽

Arc Melting ◽

Transmission Electron ◽

Master Alloys ◽

Melt Spun ◽

Melt Spun Ribbons ◽

Double Chamber

The aim of the work was to investigate the influence of the processing on the final microstructure of the melt-spun Ni-Fe-P ribbons. The melt-spinning was carried out in two ways. For the first one the alloy was molten in a simple single-chamber crucible and for the second one double-chamber crucible was used. The chemical composition of the alloy molten in the single chamber was Ni40Fe40P20. The two component melt-spinning was made starting from the Ni80P20 and Fe80P20 alloys. All of the three alloys were molten in titanium gettered argon atmosphere starting from 99.95 wt % Ni, 99.95 wt % Fe, Ni-P and Fe-P master alloys in the arc melting furnace. The alloys were melt-spun in helium. The phase composition and the microstructure of the melt-spun ribbons were investigated by X-ray diffraction (XRD), a transmission electron microscope (TEM), respectively. The fracture of the specimens were observed with use of scanning electron microscope (SEM). SEM observations of the fracture surfaces show different character of the fractured samples.

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Melt spinning process and its effect on the magnetic properties and structures of SM(CO, FE, CU, ZR)Z melt-spun ribbons

2015 IEEE Magnetics Conference (INTERMAG) ◽

10.1109/intmag.2015.7157727 ◽

2015 ◽

Author(s):

Z. Liu ◽

Y. Fang ◽

W. Sun ◽

H. Chen ◽

M. Zhu ◽

...

Keyword(s):

Magnetic Properties ◽

Melt Spinning ◽

Melt Spun ◽

Spinning Process ◽

Melt Spun Ribbons

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Metastable ordered austenite in rapidly solidified Fe-Al-C alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015455x ◽

1989 ◽

Vol 47 ◽

pp. 516-517

Author(s):

J. A. Sarreal

Keyword(s):

Rapid Solidification ◽

Melt Spinning ◽

X Ray Diffraction ◽

Austenitic Phase ◽

X Ray ◽

Transmission Electron ◽

Melt Spun ◽

Melt Spun Ribbons ◽

Equilibrium Phases ◽

Rapidly Solidified

Conventionally cast Fe-Al-C alloys are extremely brittle containing combinations of ferrite, carbide and other phases. Rapid solidification has the potential of altering the microstructure to subsequently change the resulting mechanical properties. An apparent conflict exist concerning the effect of rapid solidification on the resulting microstructure of these alloys. Inoue and co-workers, using transmission electron microscopy (TEM) and electron diffraction analyses, reported the presence of several non-equilibrium phases including austenite (fcc - γ) and ordered austenite (Ll2-γ') structures on alloys containing 1.7 to 2.1 C and 6 to 12 Al in weight % (w/o) on melt spun ribbons 30 μm in thickness. Han and Choo, using x-ray diffraction analysis on 30-48 μm thick melt spun ribbons concluded that this ordered fee phase is rather an austenitic phase in which phase decomposition accompanied by sideband phenomenon had occured.Single roller melt spinning technique was used to make ribbons 35-70 μm thick and 0.5-5 mm wide. X-ray diffration analysis showed single phase austenite for samples 2-6 w/o AI and 2 w/o C. Samples with 8-10 w/o AI and 2 w/o C also showed several superlattice lines in addition to the fundamental fcc peaks.

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Melt Spinning Process and Its Effect on the Magnetic Properties and Structure of Sm (Co, Fe, Cu, Zr)z Melt-Spun Ribbons

IEEE Transactions on Magnetics ◽

10.1109/tmag.2015.2435710 ◽

2015 ◽

Vol 51 (11) ◽

pp. 1-4

Author(s):

Zhiying Liu ◽

Yikun Fang ◽

Wei Sun ◽

Hongsheng Chen ◽

Minggang Zhu ◽

...

Keyword(s):

Magnetic Properties ◽

Melt Spinning ◽

Melt Spun ◽

Spinning Process ◽

Melt Spun Ribbons

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

MRS Proceedings ◽

10.1557/proc-460-103 ◽

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.

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New method for the production of bulk amorphous materials of Nd–Fe–B alloys

Journal of Materials Research ◽

10.1557/jmr.2005.0098 ◽

2005 ◽

Vol 20 (3) ◽

pp. 563-566 ◽

Cited By ~ 16

Author(s):

Tetsuji Saito ◽

Hiroyuku Takeishi ◽

Noboru Nakayama

Keyword(s):

Electron Microscopy ◽

Amorphous Materials ◽

Room Temperature ◽

Amorphous Structure ◽

X Ray Diffraction ◽

Bulk Materials ◽

X Ray ◽

Transmission Electron ◽

Melt Spun ◽

Melt Spun Ribbons

We report a new compression shearing method for the production of bulk amorphous materials. In this study, amorphous Nd–Fe–B melt-spun ribbons were successfully consolidated into bulk form at room temperature by the compression shearing method. X-ray diffraction and transmission electron microscopy studies revealed that the amorphous structure was well maintained in the bulk materials. The resultant bulk materials exhibited the same magnetic properties as the original amorphous Nd–Fe–B materials.

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Influence of Co-Doping on Magnetic Properties and Magnetocaloric Effect of Fe–Co–Zr–Cu–B Melt-Spun Ribbons

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19099 ◽

2021 ◽

Vol 21 (4) ◽

pp. 2552-2557

Author(s):

Nguyen Hai Yen ◽

Nguyen Hoang Ha ◽

Pham Thi Thanh ◽

Nguyen Huy Ngoc ◽

Tran Dang Thanh ◽

...

Keyword(s):

Magnetic Properties ◽

Magnetocaloric Effect ◽

Melt Spinning ◽

Room Temperature ◽

Tangential Velocity ◽

Magnetic Behavior ◽

Entropy Change ◽

Co Doping ◽

Melt Spun ◽

Melt Spun Ribbons

In this work, we investigated magnetic properties and magnetocaloric effect in Fe90−xCoxZr7Cu1B2 (x = 0, 1, 2, 3 and 4) melt-spun ribbons. The ribbons were prepared by using a melt-spinning method with a tangential velocity of a copper wheel of 40 m·s-1. The obtained ribbons are almost amorphous. The alloys exhibit typical soft magnetic behavior with low coercivity at room temperature. A minor replacement of Fe by Co gives an increment in Curie temperature (TC) of the alloys to higher temperatures. The TC of the alloys increases from 242 to 342 K with an increase of x from 0 to 4. Maximum magnetic entropy change, ΔSm max, of the alloys, was found to be larger than 0.7 J·kg-1·K-1 in a magnetic field change ΔH of 12 kOe for all the concentrations of Co. High refrigerant capacitys (RC >100 J ·kg-1 with ΔH = 12 kOe) at room temperature region have been obtained for the alloys. The large magnetocaloric effect near room temperature suggests that the alloys can be considered as magnetic refrigerants in the range of 250–350 K.

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Optimization of Manufacturing Parameters for Melt Spun Yarns Using Taguchi Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.4264 ◽

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.

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