Stability and Phase Transformations of Icosahedral Phase in a 41.5Zr41.5Ti17Ni Alloy

2000 ◽  
Vol 15 (4) ◽  
pp. 892-897 ◽  
Author(s):  
S. Yi ◽  
D. H. Kim
Keyword(s):  
Phase I ◽  
Phase Transformations ◽  
Phase Stability ◽  
Melt Spinning ◽  
Annealing Treatment ◽  
Icosahedral Phase ◽  
Melt Spun ◽  
Intermediate States ◽  
Melt Spun Ribbons ◽  
Melt Spinning Technique

Phase stability and transformations of the icosahedral phase (I-phase) in a 41.5Zr41.5Ti17Ni alloy were investigated using melt-spun ribbons and arc-melted bulk samples. A perfect I-phase can be formed directly from liquid through the melt-spinning technique. The I-phase formed in the ribbon is thermodynamically stable and transforms to W-phase, a 1/1 rational approximant above 565 °C. Formation of the perfect I-phase during annealing treatment of the arc-melted sample is very sluggish. Various types of approximants exist as intermediate states for the transformation of crystalline phases to a perfect I-phase.

Study of Two-Way Shape Memory Behavior of Amorphous-Crystalline TiNiCu Melt-Spun Ribbons

2013 ◽  
Vol 738-739 ◽  
pp. 352-356 ◽  
Author(s):  
Alexander Shelyakov ◽  
Nikolay Sitnikov ◽  
Sergey Saakyan ◽  
Alexey Menushenkov ◽  
Razhudin Rizakhanov ◽  
...  
Keyword(s):  
Experimental Data ◽  
Shape Memory ◽  
Martensite Transformation ◽  
Melt Spinning ◽  
Shape Recovery ◽  
Electrochemical Polishing ◽  
Melt Spun ◽  
Melt Spun Ribbons ◽  
The Relationship ◽  
Melt Spinning Technique

Recently we reported on the development of a composite material exhibiting reversible shape memory effect. A Ti–25Ni–25Cu (at.%) alloy was obtained by the melt spinning technique as amorphous–crystalline ribbons with a thickness of approximately 40 μm. The thickness of the amorphous and crystalline layers (dа and dc, respectively) was varied by electrochemical polishing. It has been ascertained that with varying the relationship dc/dа the martensite transformation and shape-recovery temperatures do not actually change, while the minimum radius of the ribbon bending decreases from 8.0 mm to 2.4 mm with increasing the relationship dc/dа from 0.33 to 1.40. The maximum reversible strain comprises 0.4% at dc/dа = 0.82. On the basis of experimental data obtained the phenomenological description, providing an explanation for nature of the phenomena taking place in the rapidly quenched amorphous-crystalline ribbon composite, has been proposed.

The effect of rapid solidification and grain size on the transformation temperatures of Ni-44,8wt%Ti melt spun alloy

2012 ◽  
Vol 1373 ◽  
Author(s):  
G. C. S. Anselmo ◽  
W. B. de Castro ◽  
C. J. de Araújo
Keyword(s):  
Differential Scanning Calorimetry ◽  
Grain Size ◽  
Martensitic Transformation ◽  
Rapid Solidification ◽  
Melt Spinning ◽  
Scanning Calorimetry ◽  
Transformation Temperatures ◽  
Melt Spun ◽  
Melt Spun Ribbons ◽  
Melt Spinning Technique

ABSTRACTRibbons of the Ni-44.8wt%Ti shape memory alloy are prepared through the melt spinning technique. The study is focused on investigating the effect of the rapid solidification and grain size at characteristic start martensitic (Ms), final martensitic (Mf), start austenite (As) and final austenite (Af) transformation temperatures. Changes on martensitic transformation temperatures in Ti45Ni55 melt spun ribbons are observed as grain size is reduced. Results of optical microscopy and differential scanning calorimetry (DSC) are used to associate grain size with transformation temperatures.

Rapidly Solidified Melt-spun Bi-Sn Ribbons: Surface Composition Issues

2016 ◽  
pp. 3287-3297
Author(s):  
Tarek El Ashram ◽  
Ana P. Carapeto ◽  
Ana M. Botelho do Rego
Keyword(s):  
Chemical Composition ◽  
Optical Microscopy ◽  
Melt Spinning ◽  
Surface Composition ◽  
Electrochemical Process ◽  
Melt Spun ◽  
Bismuth Alloy ◽  
The One ◽  
Rapidly Solidified ◽  
Melt Spinning Technique

Tin-bismuth alloy ribbons were produced using melt-spinning technique. The two main surfaces (in contact with the rotating wheel and exposed to the air) were characterized with Optical Microscopy and AFM, revealing that the surface exposed to the air is duller (due to a long-range heterogeneity) than the opposite surface. Also the XPS chemical composition revealed many differences between them both on the corrosion extension and on the total relative amounts of tin and bismuth. For instance, for the specific case of an alloy with a composition Bi-4 wt % Sn, the XPS atomic ratios Sn/Bi are 1.1 and 3.7 for the surface in contact with the rotating wheel and for the one exposed to air, respectively, showing, additionally, that a large segregation of tin at the surface exists (nominal ratio should be 0.073). This segregation was interpreted as the result of the electrochemical process yielding the corrosion products.

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.

Significant enhancement in thermoelectric performance of nanostructured higher manganese silicides synthesized employing a melt spinning technique

Nanoscale ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 1970-1977 ◽  
Author(s):  
Saravanan Muthiah ◽  
R. C. Singh ◽  
B. D. Pathak ◽  
Piyush Kumar Avasthi ◽  
Rishikesh Kumar ◽  
...  
Keyword(s):  
Melt Spinning ◽  
Thermoelectric Performance ◽  
Significant Enhancement ◽  
Cooling Rates ◽  
Higher Manganese Silicides ◽  
Melt Spun ◽  
Spark Plasma ◽  
High Cooling Rates ◽  
Melt Spinning Technique

An unprecedented ZT ∼ 0.82 realized in spark plasma sintered Al-doped MnSi1.73 HMS, melt spun at high cooling rates.

Recrystallization of Amorphous or Nanocrystalline NdBa2Cu3O7−x and GdBa2Cu3O7−x

1992 ◽  
Vol 275 ◽  
Author(s):  
T. J. Folkerts ◽  
S. I. Yoo ◽  
Youwen Xu ◽  
M. J. Kramer ◽  
K. W. Dennis ◽  
...  
Keyword(s):  
Melt Spinning ◽  
Amorphous Matrix ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Temperature Xrd ◽  
Melt Spun ◽  
Temperature Heat ◽  
Higher Temperature ◽  
Xrd Studies ◽  
Melt Spinning Technique

ABSTRACTUsing a novel melt-spinning technique, we have produced highly disordered NdBa2Cu3O7−x and GdBa2Cu3Oy−x materials. Samples which were melt-spun in an O2 environment consist of nanocrystals with the tetragonal REBa2Cu3O7−x structure: samples which were processed in an N2 environment consist of an amorphous matrix with small amounts of crystalline BaCu2O2, as shown by x-ray diffraction and electron microscopy. High temperature XRD studies indicate that the BaCu2O2 is eliminated during heating to 500°C in O2 and that the REBa2Cu3O7−x Phase recrystallizes directly from the amorphous matrix at temperatures below 800°C. Preliminary magnetization measurements show that higher temperature heat treatments are needed to restore superconductivity.

Effect of Rotation Speed on Transformation Behavior in Ti-48at%Ni Shape Memory Alloy Melt-Spun Ribbon

2007 ◽  
Vol 561-565 ◽  
pp. 1481-1484 ◽  
Author(s):  
Hong Yan Xing ◽  
Hee Young Kim ◽  
Shuichi Miyazaki
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Melt Spinning ◽  
Rotation Speed ◽  
Treatment Temperature ◽  
Transformation Behavior ◽  
Melt Spun ◽  
B2 Phase ◽  
Melt Spun Ribbons ◽  
Effects Of Rotation

Effects of rotation speed on the microstructure and transformation behavior were investigated for Ti-48at%Ni melt-spun ribbons. The Ti-48at%Ni shape memory alloy ribbons were fabricated by the melt-spinning method with various rotation speeds ranging from 2500rpm to 7500rpm. The melt-spun ribbons were completely crystallized to TiNi B2 phase during solidification at lower rotation speeds less than 4000rpm. Amorphous and B2 phase coexisted in the melt-spun ribbons fabricated at higher rotation speeds of 5000rpm and 7500rpm. The martensitic transformation behavior was investigated both in the as-spun and heat-treated ribbons. The transformation temperature increased with decreasing cooling rate and increasing heat-treatment temperature.

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

2013 ◽  
Vol 203-204 ◽  
pp. 361-367 ◽  
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.

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.

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