Effect of Boron on the Amorphization of Zr-Ti-Ni-Cu Alloy

1994 ◽  
Vol 38 ◽  
pp. 763-767
Author(s):  
J. D. Makinson ◽  
R. J. De Angelis ◽  
S. C. Axtell
Keyword(s):  
Mechanical Alloying ◽  
Weight Percent ◽  
High Energy ◽  
Mechanically Alloyed ◽  
Crystalline Materials ◽  
Powder Consolidation ◽  
Cu Alloy ◽  
Structure Changes ◽  
Powder Particles ◽  
New Compounds

Abstract The mechanical alloying process continually deforms, cold welds, and breaks apart metal powder particles. During the process of mechanical alloying elemental crystalline powders can produce an amorphous alloyed powder. Consolidation of these powders by powder metallurgy techniques can produce amorphous bulk metals. Two Alloys 62.24 Zr-10.89 Ti-9.71 Ni-13.14 Cu-4.02 B and 64.84 Zr-11.35 Ti-11.12 Nt-13.69 Cu weight percent were mechanically alloyed for 45 hours by a SPEX 800 high energy ball-mill. The changes in structure were monitored by X-ray diffraction after every 5 hours of milling. Both powder compositions became amorphous after 15 hours of milling. New compounds began to form during milling to 35 hours. Milling for longer times produced no further structure changes. The milled samples were annealed at 950°C for 1 hour which produced a complex set of crystalline materials. The crystalline phases containing boron have larger lattice parameters and less tendency for grain growth.

Microstructural evolution in mechanically alloyed Nb-25 at.% Ge

1986 ◽  
Vol 44 ◽  
pp. 556-557
Author(s):  
E.A. Kenik ◽  
R.B. Bayuzick ◽  
M.S. Kim ◽  
C.C. Koch
Keyword(s):  
Mechanical Alloying ◽  
Microstructural Evolution ◽  
Rapid Heating ◽  
High Energy ◽  
Mechanically Alloyed ◽  
Heating And Cooling ◽  
High Energy Ball Mill ◽  
Powder Particles ◽  
Energy Ball ◽  
Germanium Powder

Mechanical alloying involves the mixing and milling of compositionally different powders in a high energy ball mill. During this process, powder particles cold-weld to others upon impact and subsequently fracture. The coldwelding (which may involve local melting or at least elevated temperature just after impact) produces a zone of intermediate composition. As a result of the rapid heating and cooling of the interdiffused zone and the large amount of strain energy stored in the powder, mechanical alloying may produce metastable materials. The current study involves the microstructural evolution in mechanically alloyed elemental niobium and germanium powder blends.

scholarly journals Effect of Milling Parameters on the Development of a Nanostructured FCC–TiNb15Mn Alloy via High-Energy Ball Milling

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1225
Author(s):  
Cristina García-Garrido ◽  
Ranier Sepúlveda Sepúlveda Ferrer ◽  
Christopher Salvo ◽  
Lucía García-Domínguez ◽  
Luis Pérez-Pozo ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Mill ◽  
Milling Time ◽  
High Energy ◽  
Planetary Mill ◽  
Nominal Composition ◽  
Mechanically Alloyed ◽  
Milling Parameters ◽  
Energy Ball ◽  
Full Conversion

In this work, a blend of Ti, Nb, and Mn powders, with a nominal composition of 15 wt.% of Mn, and balanced Ti and Nb wt.%, was selected to be mechanically alloyed by the following two alternative high-energy milling devices: a vibratory 8000D mixer/mill® and a PM400 Retsch® planetary ball mill. Two ball-to-powder ratio (BPR) conditions (10:1 and 20:1) were applied, to study the evolution of the synthesized phases under each of the two mechanical alloying conditions. The main findings observed include the following: (1) the sequence conversion evolved from raw elements to a transitory bcc-TiNbMn alloy, and subsequently to an fcc-TiNb15Mn alloy, independent of the milling conditions; (2) the total full conversion to the fcc-TiNb15Mn alloy was only reached by the planetary mill at a minimum of 12 h of milling time, for either of the BPR employed; (3) the planetary mill produced a non-negligible Fe contamination from the milling media, when the highest BPR and milling time were applied; and (4) the final fcc-TiNb15Mn alloy synthesized presents a nanocrystalline nature and a partial degree of amorphization.

Nanoindentation Characterization of Mechanically Alloyed Fe-Al-Si Powders

2018 ◽  
Vol 784 ◽  
pp. 15-20 ◽  
Author(s):  
Petr Haušild ◽  
Jaroslav Čech ◽  
Miroslav Karlík ◽  
Filip Průša ◽  
Pavel Novák ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Alloying ◽  
Preparation Technique ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Microstructure And Mechanical Properties ◽  
Plasma Sintering ◽  
Special Sample Preparation ◽  
Spark Plasma ◽  
Powder Particles

The effect of processing conditions on microstructure and mechanical properties of Fe-Al-Si powders was studied by means of scanning electron microscopy, X-ray diffraction and nanoindentation. Fe-Al-Si alloy powder was prepared from pure elemental powders by mechanical alloying. Microstructure and mechanical properties of powders were characterized after various durations of mechanical alloying. Special sample preparation technique was developed allowing to characterize the properties of individual powder particles after each step of processing in a planetary ball mill. This step-by-step characterization allowed to find the optimum conditions for subsequent spark plasma sintering.

scholarly journals Effects of Mo Concentration on the Structural and Corrosion Properties of Cu–Alloy

Metals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1307
Author(s):  
Oscar Hernández ◽  
Claudio Aguilar ◽  
Ariosto Medina
Keyword(s):  
Mechanical Alloying ◽  
Load Transfer ◽  
High Energy ◽  
Corrosion Properties ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Electrochemical Tests ◽  
Cu Alloy ◽  
Transmission Electron ◽  
Electron Microscopy Analysis

Mechanical Alloying (MA) has the ability to extend the solubility limits of immiscible alloys in a solid state. In this work, a Cu-10 wt% Mo alloy was synthesized by mechanical alloying, using a high-energy mill type SPEX. The X-ray diffraction and Rietveld results show a crystallite size of 24 and 22 nm of Cu and Mo, respectively, with an occupation value of Mo inside the Cu structure of 27%, which was identificated by Energy Dispersive X-ray Spectroscopy and High-Resolution Transmission Electron Microscopy analysis. After that, the alloy was sinterized in an oven, heating the alloy to 1000 °C—close to the melting point of Cu (1085 °C). Electrochemical tests were carried out under a saline environment of synthetic seawater. The results show that the polarization curve of the alloy showed a pitting corrosion at about 134.83 mV, as well as a repasivation phenomenon (Erp = 241.47 mV) in the cathodic branch. Finally, three time constants were observed in the Nyquist diagrams: formation of a corrosion product film, load transfer, and diffusion, indicating that the corrosion properties in this alloy were improved compared with other Cu–alloys.

Synthesis of Cathode Materials Fe-Doped NiS2 by Mechanical Alloying for Li/NiS2 Cells

2011 ◽  
Vol 287-290 ◽  
pp. 1428-1432
Author(s):  
Xiao Jing Liu ◽  
Dong Wook Park ◽  
Zhe Zhu Xu ◽  
Sang Dae Kang ◽  
In Shup Ahn ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Cathode Materials ◽  
Lithium Ion ◽  
High Energy ◽  
Milling Process ◽  
High Energy Density ◽  
Tetraethylene Glycol ◽  
Wet Milling ◽  
Powder Particles ◽  
Normal Hexane

In order to synthesize the fine compound iron-doped nickel disulfide (NiS2) with environmentally friendly nickel, sulfur and iron powders, mechanical alloying (MA) was conducted for 8 hrs with SPEX Mill at a speed of 1000 rpm. In this process, stearic acid was added as a kind of process control agents (PCAs) to prevent the excessive cold welding. Meanwhile, for the purpose of getting nanocrystalline of Fe-doped NiS2powder particles to improve the contact areas between the active materials, the wet milling process was also done for 30 hrs with normal hexane (C6H14) as a solvent PCA. The prepared powders were characterized by FE-SEM, XRD, EPMA, EDS and TEM. Finally, the charge/discharge properties of Li/Fe-doped NiS2cells were investigated at room temperature by employing 1 M LiCF3SO3(lithium trifluoromethanesulfonate) dissolved in TEGDME (tetraethylene glycol dimethylether) as the electrolyte. The initial discharge capacity of Li/Fe-doped NiS2cell using wet milled powders as the cathode material is 792 mAh/g, which may indicate its high energy density and good future as cathode materials for lithium-ion batteries.

Effect of Microstructure of Mo-Cu Alloy on the Thermal Expansion Coefficient

2013 ◽  
Vol 873 ◽  
pp. 67-71 ◽  
Author(s):  
Zeng Feng Li ◽  
Hai Yan Liu ◽  
Ai Jun Li ◽  
Han Liang Zhang ◽  
Yuan Ping Huang ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Mechanical Alloying ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
High Energy ◽  
Fine Grained ◽  
Cu Alloy ◽  
Sealing Material ◽  
Lower Temperature ◽  
A Minor

Mo-Cu alloy with high density can be fabricated at lower sintering temperature by high-energy ball-milling mechanical-alloying method and adding activation element. The rule of change of microstructure and its effect on the thermal expansion coefficient are studied. It is found that the holes in the Mo-Cu alloy sintered at lower temperature disappear, and Mo and Cu distribute uniformly. The Mo particles are fine-grained, and distribute uniformly in the Cu particles using the mechanical-alloying method. The change of thermal expansion coefficient with temperature is in accordance with the effect of adding activation element. There is a minor inflexion in the thermal expansion coefficient curve at 500°C. The change of thermal expansion coefficient with temperature is the same as 95% Al2O3 sealing material. Thus, the thermal property between Mo-Cu alloy and 95% Al2O3 match well.

scholarly journals Formation of nanocrystalline B2-structured (Fe,Ni)Al in mechanically alloyed Fe50Al30Ni20 (wt.%) powder

2018 ◽  
pp. 66
Author(s):  
Nakib Chafika
Keyword(s):  
Dislocation Density ◽  
Mechanical Alloying ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Sem Images ◽  
X Ray ◽  
Paramagnetic Behaviour ◽  
Powder Particles ◽  
Bcc Phase

B2-structured (Fe,Ni)Al was synthesised by an abrupt reaction during mechanical alloying (MA) of the elemental powders of Fe, Al and Ni. The structural, microstructural, morphological and magnetic changes occurring in the studied material during MA were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Two crystalline phases were found, a majority one corresponding to (Fe,Ni)Al bcc phase with a crystallite size less than 10 nm, a lattice strain up to 1.6% and a dislocation density of about 2.3 x1016 m-2. The other phase was in a low proportion corresponding to Fe (Al,Ni) solid solution. SEM images showed an irregular morphology of powder particles. Mossbauer spectra of the milled powders, recorded at room temperature, reveal the paramagnetic behaviour of the obtained powder. Keywords: Mechanical alloying, ternary composition, dislocation density, structural properties, paramagnetic behaviour.

scholarly journals Crystal Structure Evolution, Microstructure Formation, and Properties of Mechanically Alloyed Ultrafine-Grained Ti-Zr-Nb Alloys at 36≤Ti≤70 (at. %)

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 587 ◽  
Author(s):  
Marczewski ◽  
Miklaszewski ◽  
Maeder ◽  
Jurczyk
Keyword(s):  
Crystal Structure ◽  
Mechanical Alloying ◽  
Pure Titanium ◽  
Young Modulus ◽  
High Energy ◽  
Structure Evolution ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Ultrafine Grained ◽  
Energy Ball

Titanium β-type alloys are preferred biomaterials for hard tissue replacements due to the low Young modulus and limitation of harmful aluminum and vanadium present in the commercially available Ti6Al4V alloy. The aim of this study was to develop a new ternary Ti-Zr-Nb system at 36≤Ti≤70 (at. %). The technical viability of preparing Ti-Zr-Nb alloys by high-energy ball-milling in a SPEX 8000 mill has been studied. These materials were prepared by the combination of mechanical alloying and powder metallurgy approach with cold powder compaction and sintering. Changes in the crystal structure as a function of the milling time were investigated using X-ray diffraction. Our study has shown that mechanical alloying supported by cold pressing and sintering at the temperature below α→β transus (600°C) can be applied to synthesize single-phase, ultrafine-grained, bulk Ti(β)-type Ti30Zr17Nb, Ti23Zr25Nb, Ti30Zr26Nb, Ti22Zr34Nb, and Ti30Zr34Nb alloys. Alloys with lower content of Zr and Nb need higher sintering temperatures to have them fully recrystallized. The properties of developed materials are also engrossing in terms of their biomedical use with Young modulus significantly lower than that of pure titanium.

Pack-Aliting in Thermitic Powder Mixture Obtained by Mechanical Alloying

2018 ◽  
Vol 69 (8) ◽  
pp. 2092-2096
Author(s):  
Mihai Branzei ◽  
Leontin Nicolae Druga ◽  
Florica Tudose ◽  
Roxana Trusca ◽  
Mihai Ovidiu Cojocaru
Keyword(s):  
Mechanical Alloying ◽  
High Energy ◽  
Reduction Reaction ◽  
Treatment Temperature ◽  
Ball Mills ◽  
Mechanically Alloyed ◽  
Aluminum Powders ◽  
Energy Ball ◽  
Nonferrous Alloys

The paper deals with the effects of the structural state modification of the main pulverulent component used for the alloying of metallic products made of steels, cast iron or nonferrous alloys, on the layers kinetics formation. The aliting process is most often done in a powdery mixtures, composed of three components: the active component providing aluminum, a neutral one with the role of dispersing the others, also having the role of blocking the sintering tendency and a halide as an activator, by cleaning the metal surfaces to be saturated. The aim of the paper is to present the ways to ensure the kinetics of the aliting layer formation, while reducing the heat treatment temperature. These could be accomplished by replacing the aluminum or ferroaluminum powder with equimassic amounts mixture of thermitic powders, consisting of ferrous oxides and aluminum powders, mechanically alloyed in high energy ball mills. Thus, it is possible to produce the aluminothermic reduction reaction in the component obtained by mechanical alloying at the same time generating notable thermal effects.

FABRICATION AND CHARACTERIZATION OF NANOSTRUCTURED CU-15WT.% MO COMPOUND BY MECHANICAL ALLOYING

2012 ◽  
Vol 05 ◽  
pp. 456-463
Author(s):  
Soheil Sabooni ◽  
Tayebeh Mousavi ◽  
Fathallah Karimzadeh
Keyword(s):  
Solid Solution ◽  
Mechanical Alloying ◽  
Structural Evolution ◽  
Weight Percent ◽  
Chromium Steel ◽  
X Ray Diffraction ◽  
Milling Operation ◽  
Powder Particles ◽  
Solid Solution Matrix

In the present study nanostructured Cu ( Mo ) compound with 15 weight percent Mo was produced by mechanical alloying using a planetary ball mill. The milling operation was carried out in hardened chromium steel vial and balls under argon atmosphere with a constant ball to powder ratio of 10:1. The structural evolution and characterization of powder particles after different milling times were studied by X-Ray Diffraction, SEM observation and Microhardness measurements. The results showed the displacement of broadened Cu peaks to lower angles, because of dissolving Mo in Cu . The final product was a nanocomposite contains nanocrystalline Cu ( Mo ) supersaturated solid solution matrix and dispersion of nanometric Mo reinforcements. The microhardness of formed nanocomposite increased to 350HV because of grain refinement, formation of solid solution and dispersion hardening.

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