scholarly journals Structural Evolution of Nano-sized Oxide Particles Formed in Mechanically Alloyed Fe-10Cr-5Y2O3 Powders

Metals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 310
Author(s):  
Ga Eon Kim ◽  
Tae Kyu Kim ◽  
Sanghoon Noh
Keyword(s):  
Heat Treatment ◽  
Phase Transformation ◽  
Mechanical Alloying ◽  
Morphological Change ◽  
Ball Mill ◽  
Structural Evolution ◽  
Oxide Phase ◽  
High Energy ◽  
Mechanically Alloyed ◽  
Oxide Particles

Fe-10Cr-5Y2O3 powders were mechanically alloyed using a high energy horizontal ball-mill apparatus, and the effect of heat treatment on the behavior of nano-sized oxide particles formed in the mechanically alloyed Fe-10Cr-5Y2O3 powders was investigated. Elongated Cr-rich and Y-rich oxides were observed in the mechanically alloyed powders. During the heating of these powders above 700 °C, the elongated Cr-rich oxides were dramatically changed to a near- spherical morphology. Cubic-Y2O3, monoclinic-Y2O3 and YFeO3 phases were also found after heat treatment at 1150 °C for 1h, indicating that the Y-rich oxide phase was transformed to the cubic-Y2O3, monoclinic-Y2O3 and YFeO3 ones. It is thus concluded that both a morphological change of Cr-rich oxide and a phase transformation of Y-rich oxide during the heating of mechanically alloyed powders could be mainly attributed to extremely high energy, accumulated by the mechanical alloying process.

Structural Evolution of Mechanically Alloyed Nanocrystalline Al70Fe25Ni5 Intermetallics

2013 ◽  
Vol 275-277 ◽  
pp. 1751-1754
Author(s):  
Zhang Jing ◽  
Qi Zhi Cao ◽  
Zheng Liang Li
Keyword(s):  
Mechanical Alloying ◽  
Solid Solutions ◽  
Ball Mill ◽  
Structural Changes ◽  
Structural Evolution ◽  
High Energy ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
X Ray ◽  
Scanning Electron

Nanostructured Al-25at.%Fe-5at.%Ni intermetallics were prepared directly by mechanical alloying (MA) in a high-energy planetary ball-mill. The phase transformations and structural changes occurring in the studied material during mechanical alloying were investigated by X-ray diffraction (XRD). Scanning electron microscopy (SEM) was employed to examine the morphology of the powders. Thermal behavior of the milled powders was examined by differential thermal analysis (DTA). The solid solutions of Fe (Al) and Ni (Fe) in the Al70Fe25Ni5 system are observed at the early milling stage. The solid solutions transforms into amorphous and disordered Al (Fe, Ni) phase. The last milling products in the Al70Fe25Ni5 system are Al3Ni2, AlFe3 and AlFe0.23Ni0.77 phases.

Structural Evolution of Mechanically Alloyed Nanocrystalline Fe25Al50Ni25 Intermetallics

2012 ◽  
Vol 476-478 ◽  
pp. 1476-1479
Author(s):  
Qi Zhi Cao ◽  
Jing Zhang ◽  
Jian Ying Li
Keyword(s):  
Solid Solution ◽  
Mechanical Alloying ◽  
Ball Mill ◽  
Structural Changes ◽  
Structural Evolution ◽  
High Energy ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
X Ray ◽  
Unknown Phase

Nanostructured Fe25Al50Ni25intermetallics was prepared directly by mechanical alloying (MA) in a high-energy planetary ball-mill. The phase transformations and structural changes occurring in the studied material during mechanical alloying were investigated by X-ray diffraction (XRD). Thermal behavior of the milled powders was examined by differential thermal analysis (DTA). Disordered Al(Fe,Ni) solid solution was formed After 50 h of milling. Al(Fe,Ni) solid solution milled for 100h transformed into FeNi,FeNi3 and AlNi3 phase. The power annealed at temperature 500 results in forming of intermetallics AlFe0.23Ni0.77, Al1.1Ni0.9 , AlNi and two unknown phase after 5h milling. The nanocrystalline metallic compound was obtained after 100h milling.

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.

scholarly journals Synthesis of the Mg2Ni Alloy Prepared by Mechanical Alloying Using a High Energy Ball Mill

2019 ◽  
Vol 54 (1) ◽  
Author(s):  
José Luis Iturbe-García ◽  
Manolo Rodrigo García-Núñez ◽  
Beatriz Eugenia López-Muñoz
Keyword(s):  
Mechanical Alloying ◽  
Ball Mill ◽  
Structural Changes ◽  
Weight Ratio ◽  
Structural Evolution ◽  
High Energy ◽  
Process Time ◽  
High Energy Ball Mill ◽  
Energy Ball ◽  
Steel Balls

Mg2Ni was synthesized by a solid state reaction from the constituent elemental powder mixtures via mechanical alloying. The mixture was ball milled for 10 h at room temperature in an argon atmosphere. The high energy ball mill used here was fabricated at ININ. A hardened steel vial and three steel balls of 12.7 mm in diameter were used for milling. The ball to powder weight ratio was 10:1. A small amount of powder was removed at regular intervals to monitor the structural changes. All the steps were performed in a little lucite glove box under argon gas, this glove box was also constructed in our Institute. The structural evolution during milling was characterized by X-ray diffraction and scanning electron microscopy techniques. The hydrogen reaction was carried out in a micro-reactor under controlledconditions of pressure and temperature. The hydrogen storage properties of mechanically milled powders were evaluated by using a TGA system. Although homogeneous refining and alloying take place efficiently by repeated forging, the process time can be reduced to one fiftieth of the time necessary for conventional mechanical milling and attrition.        

Phase Transformation and Synthesis of Ni Substituted CoSb3 Skutterudite Synthesis during Solid State Reaction

2005 ◽  
Vol 475-479 ◽  
pp. 857-860 ◽  
Author(s):  
Jun You Yang ◽  
Yuehua Chen ◽  
Jiangying Peng ◽  
Wen Zhu ◽  
Xin Li Song
Keyword(s):  
Phase Transformation ◽  
Solid State ◽  
Mechanical Alloying ◽  
Solid State Reaction ◽  
Ball Mill ◽  
Single Phase ◽  
Lattice Parameter ◽  
Maximum Solubility ◽  
Mechanically Alloyed ◽  
Skutterudite Compound

Starting from elemental Co (99.9%), Ni (99.9%) and Sb (99.99%) powders, Co4-xNixSb12 powder mixture with different Ni concentration were subjected to mechanical alloying by using a planetary ball mill. Phase transformation during mechanical alloying process of Co-Ni-Sb system was studied in this paper. Ni substituted skutterudite could be synthesized by solid state reaction. With assistance of hot pressing for two hours, the as mechanically alloyed low Ni concentration powders could be completely transformed into skutterudite compound. The lattice parameter of Ni substituted skutterudite compound complies well with Vegard law when x is not more than 0.2. When Ni concentration is larger than the maximum solubility, NiSb2 compound forms and single phase skutterudite compound can not be obtained.

scholarly journals Influence of V and Heat Treatment on Characteristics of WMoNbTaV Refractory High-Entropy Alloy Coatings by Mechanical Alloying

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 265
Author(s):  
Chun-Liang Chen ◽  
Sutrisna
Keyword(s):  
Heat Treatment ◽  
Mechanical Alloying ◽  
Annealing Treatment ◽  
High Energy ◽  
304 Stainless Steel ◽  
Homogeneous Distribution ◽  
High Entropy Alloy ◽  
Solid Solution Phase ◽  
High Entropy ◽  
Steel Substrates

Refractory high-entropy alloy (RHEA) is one of the most promising materials for use in high-temperature structural materials. In this study, the WMoNbTaV coatings on 304 stainless steel substrates has been prepared by mechanical alloying (MA). Effects of V addition and subsequent heat treatment on properties of the WMoNbTaV coatings were investigated. The results show that the RHEA coatings with nanocrystalline body-centered cubic (BCC) solid-solution phase were generated by the mechanical alloying process. The presence of the V element promotes a uniform microstructure and homogeneous distribution of composition in the RHEA coatings due to improving alloying efficiency, resulting in an increase of hardness. After the annealing treatment of the RHEA coatings, microstructure homogeneity was further enhanced; however, the high affinity of Ta for oxygen causes the formation of Ta-rich oxides. Annealing also removes strain hardening generated by high-energy ball milling and thus decreases the hardness of the RHEA coating and alters microstructure evolution and mechanical properties.

scholarly journals Structural Evolution in Wet Mechanically Alloyed Co-Fe-(Ta,W)-B Alloys

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 800
Author(s):  
Vladimír Girman ◽  
Maksym Lisnichuk ◽  
Daria Yudina ◽  
Miloš Matvija ◽  
Pavol Sovák ◽  
...  
Keyword(s):  
Structural Changes ◽  
Magnetic Measurements ◽  
Structural Evolution ◽  
High Energy ◽  
Control Agent ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
X Ray ◽  
Transmission Electron ◽  
X Ray Absorption

In the present study, the effect of wet mechanical alloying (MA) on the glass-forming ability (GFA) of Co43Fe20X5.5B31.5 (X = Ta, W) alloys was studied. The structural evolution during MA was investigated using high-energy X-ray diffraction, X-ray absorption spectroscopy, high-resolution transmission electron microscopy and magnetic measurements. Pair distribution function and extended X-ray absorption fine structure spectroscopy were used to characterize local atomic structure at various stages of MA. Besides structural changes, the magnetic properties of both compositions were investigated employing a vibrating sample magnetometer and thermomagnetic measurements. It was shown that using hexane as a process control agent during wet MA resulted in the formation of fully amorphous Co-Fe-Ta-B powder material at a shorter milling time (100 h) as compared to dry MA. It has also been shown that substituting Ta with W effectively suppresses GFA. After 100 h of MA of Co-Fe-W-B mixture, a nanocomposite material consisting of amorphous and nanocrystalline bcc-W phase was synthesized.

scholarly journals Influence of Preparation Process on Microstructure, Critical Current Density and Tc of MgB2/Fe/Cu Wires

2007 ◽  
Vol 546-549 ◽  
pp. 2031-2034
Author(s):  
Y.F. Wu ◽  
G. Yan ◽  
J.S. Li ◽  
Y. Feng ◽  
Shao Kai Chen ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Current Density ◽  
Rolling Process ◽  
High Energy ◽  
Transport Current ◽  
Post Heat Treatment ◽  
Mechanically Alloyed ◽  
Mgb2 Wires ◽  
Powder In Tube ◽  
Transport Current Density

The powder-in-tube MgB2 wires were prepared by high energy milling of Mg and B powder. The powder was not mechanically alloyed for 2h short milling time. However, the MgB2 grains in wires were very small (20~100nm) and resemble the dimple after post-heat treatment. The clear evidence for transcrystlline fracture was observed. It indicated that the grain connection was greatly improved and the fluxing pinning was significantly enhanced. Another point to view was no intermediate annealing during the whole rolling process. The influence of the post-heat treatment on the transport current density was studied. Despite the lower Tc of about 35K, the transport current density reached to 3×104A/cm2 at 15K and 3.5T for wires sintered at 700°C.

SYNTHESIS OF NANO-CRYSTALLINE Cu-Cr ALLOY BY MECHANICAL ALLOYING

2012 ◽  
Vol 05 ◽  
pp. 496-501 ◽  
Author(s):  
S. SHEIBANI ◽  
S. HESHMATI-MANESH ◽  
A. ATAIE
Keyword(s):  
Mechanical Alloying ◽  
Structural Evolution ◽  
High Energy ◽  
Lattice Parameter ◽  
Control Agent ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Nano Crystalline ◽  
High Energy Ball Mill ◽  
Energy Ball

In this paper, the influence of toluene as the process control agent (PCA) and pre-milling on the extension of solid solubility of 7 wt.% Cr in Cu by mechanical alloying in a high energy ball mill was investigated. The structural evolution and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques, respectively. The solid solution formation at different conditions was analyzed by copper lattice parameter change during the milling process. It was found that both the presence of PCA and pre-milling of Cr powder lead to faster dissolution of Cr . The mean crystallite size was also calculated and showed to be about 10 nm after 80 hours of milling.

Sign in / Sign up

Export Citation Format

Share Document