A Comparative Study of The Crystallization of Ni-P Amorphous Alloys Produced By Ion-Implantation And Melt Spinning.

1985 ◽  
Vol 51 ◽  
Author(s):  
James Hamlyn-Harris ◽  
D. H. St. John ◽  
D. K. Sood
Keyword(s):  
Amorphous Alloys ◽  
Melt Spinning ◽  
Room Temperature ◽  
Nucleation And Growth ◽  
Nominal Composition ◽  
Similar Composition ◽  
Melt Spun ◽  
Dta Analysis ◽  
Amorphous Surface ◽  
Effect Of Surface

ABSTRACTImplantation of 4OkeV P+ ions into high purity Ni was employed at room temperature to a dose of 3×10E17 ions/cm2 to produce an 1100 A thick amorphous surface alloy of Ni-14 wt% P. Commercially available melt spun metallic glass ribbons of nominal composition, Ni-il wt% P were used for comparison of crystallization behaviour studied with TEM and RBS techniques. The DTA analysis was employed to construct a TTT curve for the melt spun glass, which was then used as a guide for selecting time and temperature of crystallization of the implanted amorphous alloy. The melt implanted glass is found to be less stable and crystallizes more readily than melt spun glass of similar composition. A detailed study on nucleation and growth of crystallites, mode of crystallization and effect of surface proximity will be presented.

Spherulite Structures in a Melt Spun Fe-Ni Austenitic Steel

1985 ◽  
Vol 43 ◽  
pp. 52-53
Author(s):  
G. M. Michal ◽  
T. K. Glasgow ◽  
T. J. Moore
Keyword(s):  
Austenitic Steel ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Large Range ◽  
Amorphous Structure ◽  
Nucleation And Growth ◽  
Ni Alloys ◽  
Melt Spun ◽  
Crystal Fibers ◽  
Rapidly Solidified

Large additions of B to Fe-Ni alloys can lead to the formation of an amorphous structure, if the alloy is rapidly cooled from the liquid state to room temperature. Isothermal aging of such structures at elevated temperatures causes crystallization to occur. Commonly such crystallization pro ceeds by the nucleation and growth of spherulites which are spherical crystalline bodies of radiating crystal fibers. Spherulite features were found in the present study in a rapidly solidified alloy that was fully crysstalline as-cast. This alloy was part of a program to develop an austenitic steel for elevated temperature applications by strengthening it with TiB2. The alloy contained a relatively large percentage of B, not to induce an amorphous structure, but only as a consequence of trying to obtain a large volume fracture of TiB2 in the completely processed alloy. The observation of spherulitic features in this alloy is described herein. Utilization of the large range of useful magnifications obtainable in a modern TEM, when a suitably thinned foil is available, was a key element in this analysis.

Microstructural Studies of NiCoMnIn Magnetic Shape Memory Ribbons

2013 ◽  
Vol 738-739 ◽  
pp. 436-440 ◽  
Author(s):  
Krystian Prusik ◽  
Katarzyna Bałdys ◽  
Danuta Stróż ◽  
Tomasz Goryczka ◽  
Józef Lelątko
Keyword(s):  
Melt Spinning ◽  
Room Temperature ◽  
Parent Phase ◽  
Magnetic Shape Memory ◽  
Melt Spun ◽  
Columnar Grains ◽  
Ebsd Technique ◽  
Microstructural Studies ◽  
Melt Spinning Technique ◽  
Scanning Electron

In present paper two ribbons of the Ni44Co6Mn36In14 (at.%) were prepared under different melt-spinning technique conditions. Microstructure of the ribbons was studied by scanning electron microscopy (SEM). Depending on the liquid ejection overpressure two types of ribbons microstructures were observed. Ribbon T1 for which ejection overpressure was 1.5 bar showed typical melt-spun ribbon microstructure consisting of a top layer of small equi-axial grains and columnar grains below. For T2 ribbon (ejection overpressure 0.2 bar) only a small fraction of the columnar grains were observed. Structure analysis of the ribbons performed by XRD showed that at room temperature both ribbons have B2 parent phase superstructure. No gamma phase precipitates were observed. In order to determine the orientation of the grains the EBSD technique was applied.

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

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.

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.

The Shape Memory Effect in Melt Spun Fe-15Mn-5Si-9Cr-5Ni Alloys

2013 ◽  
Vol 738-739 ◽  
pp. 247-251 ◽  
Author(s):  
Ana Druker ◽  
Paulo La Roca ◽  
Philippe Vermaut ◽  
Patrick Ochim ◽  
Jorge Malarría
Keyword(s):  
Shape Memory ◽  
Shape Memory Effect ◽  
Memory Effect ◽  
Melt Spinning ◽  
Room Temperature ◽  
Tensile Tests ◽  
Argon Atmosphere ◽  
Austenitic Phase ◽  
Melt Spun ◽  
Shape Memory Behaviour

At room temperature, Fe-15Mn-5Si-9Cr-5Ni alloys are usually austenitic and the application of a stress induces a reversible martensitic transformation leading to a shape memory effect (SME). However, when a ribbon of this material is obtained by melt-spinning, the rapid solidification stabilizes a high-temperature ferritic phase. The goals of this work were to find the appropriate heat treatment in order to recover the equilibrium austenitic phase, characterize the ribbon form of this material and evaluate its shape memory behaviour. We found that annealing at 1050°C for 60 min, under a protective argon atmosphere, followed by a water quenching stabilizes the austenite to room temperature. The yield stress, measured by tensile tests, is 250 MPa. Shape-memory tests show that a strain recovery of 55% can be obtained, which is enough for certain applications.

Fabrication and Properties of High Strength Al-8Fe-2Mo-2V-1Zr Alloy Produced by Melt Spinning Techniques

2006 ◽  
Vol 510-511 ◽  
pp. 854-857 ◽  
Author(s):  
Taek Kyun Jung ◽  
Dong Suk Lee ◽  
Mok Soon Kim ◽  
Won Yong Kim
Keyword(s):  
Particle Size ◽  
Yield Strength ◽  
Melt Spinning ◽  
Room Temperature ◽  
Intermetallic Phase ◽  
Hot Extrusion ◽  
High Strength ◽  
Extrusion Temperature ◽  
Grain Structure ◽  
Melt Spun

High strength Al-8Fe-2Mo-2V-1Zr (wt.%) alloys fabricated by a melt spinning and a hot extrusion process were produced to correlate the microstructure and mechanical property. Melt spun ribbon prepared by single roll melt spinner showed a cellular structure with an average size of 10nm and Al-Fe based intermetallic dispersoid of less than 10nm in particle size. The melt spun ribbon obtained was then pulverized to make a powder shape followed by hot extrusion at 648K, 673K, 723K and 773K in extrusion ratio of 5 to 1, respectively. Equiaxed grain structure containing Al-Fe based intermetallic phase was observed in all extruded specimens. According to increasing extrusion temperature, the grain size increased and particle size of intermetallic dispersoid. The lattice parameter increased from 0.4051nm to 0.4059 nm with increasing extrusion temperature from 648K to 773K, those values were larger than that obtained in pure Al (0.4049nm). Yield strength of the specimen extruded at 648K measured to 956MPa at room temperature, 501MPa at 573K and 83MPa at 773K, respectively. With increasing extrusion temperature yield strength decreased significantly at room temperature and even in the intermediate temperature range, while no noticeable difference in yield strength was observed at 773K.

scholarly journals Transport And Magnetic Properties Of (Fe100-xVx)75 P15C10 Amorphous Alloys

1970 ◽  
Vol 35 (2) ◽  
pp. 161-169
Author(s):  
MAS Karal ◽  
M Kamruzzaman ◽  
FA Khan
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Saturation Magnetization ◽  
Amorphous Alloys ◽  
Melt Spinning ◽  
Room Temperature ◽  
Resistivity Measurement ◽  
Anomalous Hall Effect ◽  
Hall Resistivity ◽  
Melt Spinning Technique

(Fe100-xVx)75 P15C10 (x = 0, 5, 10 and 15) amorphous alloys in the form of ribbon were prepared by the standard melt spinning technique and studied their transport and magnetic properties. The resistivity follows ‘Mooij correlation’ at low temperature (300 - 93) K. The Hall resistivity and the magnetoresistance (MR) were measured in an applied magnetic field up to 0.6T at room temperature (RT = 300 K). Anomalous Hall effect was observed in the Hall resistivity measurement and MR was found to vary 0 - 8%. The saturation magnetization gradually decreased with the increase of V in the alloys at RT. Key words: Resistivity; Mooij correlation; Hall resistivity; Magnetoresistance; Saturation magnetization DOI: http://dx.doi.org/10.3329/jbas.v35i2.9420 JBAS 2011; 35(2): 161-169

scholarly journals Microstructure Development and Properties of the Two-Component Melt-Spun Ni55Fe20Cu5P10B10 Alloy at Elevated Temperatures

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1741
Author(s):  
Krzysztof Ziewiec ◽  
Mirosława Wojciechowska ◽  
Irena Jankowska-Sumara ◽  
Aneta Ziewiec ◽  
Sławomir Kąc
Keyword(s):  
High Temperature ◽  
Melt Spinning ◽  
Elevated Temperatures ◽  
Amorphous State ◽  
Nominal Composition ◽  
Composite Alloy ◽  
X Ray Diffraction ◽  
Heating Rates ◽  
Two Component ◽  
Melt Spun

The aim of this work was to investigate the features of microstructure, phase composition, mechanical properties, and thermal stability of the two-component melt-spun Ni55Fe20Cu5P10B10 alloy. The development of the microstructure after heating to elevated temperatures was studied using scanning electron microscope and in situ high temperature X-ray diffraction. The high-temperature behavior of the two-component melt-spun Ni55Fe20Cu5P10B10 alloy and Ni40Fe40B20, Ni70Cu10P20, and Ni55Fe20Cu5P10B10 alloys melt-spun from single-chamber crucible was investigated using differential scanning calorymetry at different heating rates and by dynamic mechanical thermal analysis. The results show that band-like microstructure of the composite alloy is stable even at 800 K, although coarsening of bands forming the microstructure of the ribbons is observed above 550 K. Plastic deformation is observed in the composite previously heated to temperatures of 600–650 K. The properties of the composite alloy are generally different than the properties obtained for the melt-spun alloy of the same average nominal composition produced traditionally. Additionally, the mechanical and the thermal properties in this composite are inherited from the amorphous state of alloys that are precursors for two-component melt spinning (TCMS) processing.

Giánt Mr in Granular Systems Prepared by Melt-Spinning and Sputtering

1993 ◽  
Vol 313 ◽  
Author(s):  
B. Dieny ◽  
S.R. Teixeira ◽  
B. Rodmacq ◽  
A. Chamberod ◽  
J.B. Genin ◽  
...  
Keyword(s):  
Melt Spinning ◽  
Room Temperature ◽  
Magnetic Particles ◽  
Spin Valve ◽  
Granular Systems ◽  
Magnetic Fluctuations ◽  
The Third ◽  
Melt Spun

ABSTRACTWc report the observation of giant magnctorcsistance in granular systems prepared by either Melt-spinning or sputtering. For Melt-spun CoxCu1-x alloys, with x varying between 5 and 30%, Magnctoresitancc amplitudes of 20% in 50 kOc at 5 K were obtained, similar to those reported for the same alloys prepared by sputtering. For sputtered (Ni80Fe20)xAg1-x alloys, three different contributions to the magnetorcsisiancc have been clearly identified: The spin-valve (or giant) Magnctorcsistance, scattering on magnetic fluctuations, and anisotropie Magnetorcsistancc. These three contributions have their own dependences on the size of the magnetic particles, on the degree of intermixing between NiFe and Ag, and on the temperature. In the third scries of samples, sputtered (Co70Fe30)xAg1-x, very large magnctorcsistance amplitude has been observed (AR/R as high as 20% at room temperature in 10 kOc and 60% at 10 K).

SPRAY FORMING OF FINEMET ALLOY FE73.5CU1NB3SI13.5B9

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1282-1287
Author(s):  
SHA YANG ◽  
BIAO YAN ◽  
PENG DONG ◽  
LEDING GUAN
Keyword(s):  
Grain Size ◽  
Amorphous Alloys ◽  
Melt Spinning ◽  
Optical Microscope ◽  
Spray Forming ◽  
Nominal Composition ◽  
Transmission Electron ◽  
Average Grain Size ◽  
Median Diameter ◽  
Scherrer Formula

Fe -based amorphous alloys are widely used in the magnetic apparatus and generally produced by the single-roller copper-wheel melt spinning method. Spray forming is one of the rapid solidification techniques as the spinning method is, seldom used to fabricate Fe -based amorphous alloys. However in this paper, a Fe -based alloy with the nominal composition of Fe 73.5 Cu 1 Nb 3 Si 13.5 B 9 ( at .%) alloy was fabricated by spray forming technique with the aim of investigating the formation of amorphous phases and novel microstructures by the high cooling rate involved in this process. The gas/metal mass flow rate used was 0.15, and nitrogen was used as the atomization gas. The resulting deposit and the overspray powder had a median diameter of about 50 μm with a total weight of about 2.2 kg. The microstructure of the deposit was observed by utilizing the X-Ray Diffraction (XRD) and Optical Microscope (OM), as well as Transmission Electron Microscope (TEM), which revealed a heterogeneous varying with the thickness, presenting at center region 15 mm and at border 8 mm with porosities 4 and 9%, respectively. The thicker region showed a fully crystalline microstructure with grain size of about 250nm, whereas the thinner region had a partially amorphous phase with an average grain size of 40nm. The overspray powder was fully crystallized with the grain size of 80nm which was calculated from XRD spectra using the Scherrer formula. The magnetic properties were measured through VSM, giving a poor magnetic saturation value of about 0.3~0.6 T . The coercive force was increased significantly.

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