Phase transformations and microstructural evolution in nanocrystalline Fe71B23Nb6 alloy prepared by mechanical alloying

2020 ◽  
Vol 111 (4) ◽  
pp. 307-315
Author(s):  
Mahmoud Chemingui ◽  
Chahida Mnasri ◽  
Christelle Nivot ◽  
Arnaud Tricoteaux ◽  
Yannick Lorgouilloux ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Alloying ◽  
Alloy Powder ◽  
Milling Time ◽  
Milling Process ◽  
Microstructural Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Prepared Alloy ◽  
Scanning Electron

Abstract A new nanocrystalline Fe71B23Nb6 alloy powder was prepared by mechanical alloying. The phase transformation and morphological and microstructural properties of the as-prepared alloy were investigated by scanning electron microscopy, laser granulometry, and X-ray diffraction with respect to the milling time (0- 200 h). During the milling process, it was observed that the dissolution of Nb and B atoms into the Fe matrix formed solid solutions of Fe (Nb), Fe (B), Fe23B6, Fe2B, and Fe (Nb, B). Moreover, the insertion of B atoms into the Nb network generated the Nb (B) phase. Furthermore, the minimum crystallite size was measured as approximately 1 nanometer. In addition, the dislocation density gradually increased with the extension of the milling time, and the crystallization of the partially amorphous phase occurred after 200 h of milling.

The Synthesis of Cu0.81Ni0.19 Intermetallics by Mechanical Alloying

2012 ◽  
Vol 496 ◽  
pp. 379-382
Author(s):  
Rui Song Yang ◽  
Ming Tian Li ◽  
Chun Hai Liu ◽  
Xue Jun Cui ◽  
Yong Zhong Jin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Elemental Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scherrer Equation ◽  
Scanning Electron

The Cu0.81Ni0.19 has been synthesized directly from elemental powder of nickel and copper by mechanical alloying. The alloyed Cu0.81Ni0.19 alloy powders are prepared by milling of 8h. The grain size calculated by Scherrer equation of the NiCu alloy decreased with the increasing of milling time. The end-product was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM)

Effect of Milling Time on the Structural Properties of Titanium Dioxide Nanopowder

2012 ◽  
Vol 229-231 ◽  
pp. 228-232
Author(s):  
N.N. Hafizah ◽  
M.F. Achoi ◽  
L.N. Ismail ◽  
M. Rusop
Keyword(s):  
Electron Microscopy ◽  
Structural Properties ◽  
Milling Time ◽  
Anatase Phase ◽  
Sol Gel ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Paper Report ◽  
X Ray ◽  
Scanning Electron

This paper report the effect of milling time on the structural properties of TiO2nanopowder prepared from sol-gel milling process. The synthesized TiO2nanopowders have been characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared (FTIR). XRD result reveals that the TiO2nanopowder in anatase phase is detected. The morphology of the TiO2nanopowder change obviously with the increase of the milling time. Further, FTIR results found the sharp peaks of Ti-O-Ti and Ti-O bonding at below 600 cm-1for all TiO2nanopowder.

Structural Evolution of the Cu-Ni Solid Solution Formed by Ball Mechanical Alloying Treatment (BMAT)

2011 ◽  
Vol 673 ◽  
pp. 279-284 ◽  
Author(s):  
Iman Farahbakhsh ◽  
Alireza Zakeri ◽  
Palavesamuthu Manikandan ◽  
Kazuyuki Hokamoto
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Structural Evolution ◽  
Mutual Diffusion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ma Process ◽  
Scanning Electron

A nanostructured powder with uniform distribution of Ni and Cu powders was produced by means of the Ball Mechanical Alloying Treatment (BMAT). Mutual diffusion of Ni and Cu in the nanostructured layer and the microstructure of the cross section of the remaining powders were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Electron Probe Microanalyzer (EPMA). X-ray diffraction patterns revealed that increasing the milling time gives rise to decreasing crystallite size and lattice parameter during the MA process. Furthermore, scanning electron microscopy (SEM) was utilized not only for evaluating the morphology and microstructure of the remaining powder particles but also for proving this claim that during MA process, the mutual diffusion of Ni and Cu has occurred. Elemental mappings also show that the alloying process occurred in samples but obtaining the uniform shape, size and microstructure of the powder requires increase in the milling time.

Dissolution of Al 6%wt c Mixture Using Mechanical Alloying

2019 ◽  
Vol 391 ◽  
pp. 82-87
Author(s):  
R. Dabouz ◽  
Meriem Bendoumia ◽  
Lounes Belaid ◽  
Mohamed Azzaz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Mechanical Alloying ◽  
Solid Solubility ◽  
Milling Time ◽  
X Ray Diffraction ◽  
Processing Methods ◽  
X Ray ◽  
Scanning Electron

In the equilibrium processing methods the system Al-C does not show any solid solubility which means that carbon is not soluble in aluminum. In this work an investigation of mechanical alloying on system Al-C was presented to force the dissolution. Using different techniques such as the X-ray diffraction and scanning electron microscopy (SEM), it was proved the force of dissolution by studying the specters for different milling time and by flowing the evolution during annealing into a DSC. Furthermore, morphology of phases has been studied.

Structural Evaluation of Ti-22.2Si-11.1B Powders Milled with PCA Addition

2008 ◽  
Vol 591-593 ◽  
pp. 147-153
Author(s):  
Gilbert Silva ◽  
Erika Coaglia Trindade Ramos ◽  
N.S. da Silva ◽  
Alfeu Saraiva Ramos
Keyword(s):  
Electron Microscopy ◽  
Ball Milling ◽  
Ball Mill ◽  
Milling Process ◽  
Argon Atmosphere ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural Evaluation ◽  
Equilibrium Structures ◽  
Scanning Electron

A large amount of the Ti6Si2B compound can be formed by mechanical alloying and subsequent heat treatment from the elemental Ti-22.2at%Si-11.1at%B powder mixture, but the yield powder after ball milling is reduced due to an excessive agglomeration of ductile particles on the balls and vial surfaces. This work reports on the structural evaluation of Ti-22.2at%Si-11.1at%B powders milled with PCA addition, varying its amount between 1 and 2 wt-%. The milling process was carried out in a planetary ball mill under argon atmosphere, and the milled powders were then heated at 1200oC for 1h under Ar atmosphere in order to obtain equilibrium structures. Samples were characterized by X-ray diffraction, scanning electron microscopy, and thermal analysis. Results revealed that the PCA addition reduced the excessive agglomeration during the ball milling of Ti-22.2at-%Si-11.1at-%B powders. After heating at 1200oC for 1h, the Ti5Si3, Ti3O and/or Ti2C phases were preferentially formed in Ti-22.2at%Si-11.1at%B powders milled with PCA addition, and the Ti6Si2B formation was inhibited.

Different Cr Contents in Nanostructured Fe-Ni-Cr Alloys Prepared by Mechanical Alloying

2012 ◽  
Vol 531-532 ◽  
pp. 437-441 ◽  
Author(s):  
Qi He ◽  
Tao Liu ◽  
Jian Liang Xie
Keyword(s):  
Particle Size ◽  
Mechanical Alloying ◽  
Ball Milling ◽  
Lattice Distortion ◽  
Milling Time ◽  
Nanocrystalline Powders ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ball Milling Time ◽  
Scanning Electron

Fe-Ni-Cr alloy powders with the different components were prepared by Mechanical Alloying (MA). The phase structure, grain size, micro-strain and lattice distortion were determined with X-ray diffraction. The morphology and particle size of the powders were observed and analyzed using a field emission scanning electron microscopy. The results showed that the Fe-Ni-Cr nanocrystalline powders could be obtained by MA. The ball milling time could be reduced with increasing amount of Cr, resulting the formation of Fe-Ni-Cr powders. With the increasing amount of Cr, the speed of Ni diffusion to Fe lattice approaching saturation became more rapid. The particle size got smaller as the ball milling went further; the extent of micro-strain and distortion of lattice intensified; the solid solubility of Ni and Cr in Fe was increased. Finally the super-saturated solid solution of Fe was obtained.

Study of Nanocrystalline NiAl Alloys Prepared by Mechanical Alloying

2012 ◽  
Vol 329 ◽  
pp. 19-28 ◽  
Author(s):  
M. Gherib ◽  
A. Otmani ◽  
A. Djekoun ◽  
A. Bouasla ◽  
M. Poulain ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Crystallite Size ◽  
Milling Time ◽  
Structural Features ◽  
Milling Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Size Refinement ◽  
20 Nm ◽  
Kinetics Of

Nanostructured Powders of Ni-20wt%Al and Ni-50wt%Al Were Prepared, by Mechanical Alloying under an Argon Atmosphere, from Elemental Ni and Al Powders Using a Planetary Ball Mill (type Fritsch P7) for Different Times (0.5-24h).). Microstructural and Structural Features of the Final Products Were Characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). the Results of the XRD Shows the Formation of the B2 (Ni Al) Phase after 2 Hours of Milling for both Systems. Also Detected Was the Ni3al Phase in Ni80al20after 4 Hours. Crystallite Size Refinement of the Final Product Occurred down to Nanometer Scales when the Milling Time Increased, and Attained 17 Nm in the Ni50al50System and 20 Nm in the other System, at 24 Hours. this Decrease in Crystallite Size Is Accompanied by an Increase in the Interval Level Strain. the Kinetics of Al Dissolution during the Milling Process of Ni50al50System Can Be Described by Two Regimes, Characterised by Different Values of Avrami Parameters which Are Calculated by Using the Johnson–Mehl–Avrami Formalism.

scholarly journals Microstructural Analysis of Silica Fume Concrete with Scanning Electron Microscopy and X-Ray Diffraction

2020 ◽  
Vol 10 (3) ◽  
pp. 5845-5850
Author(s):  
B. Uzbas ◽  
A. C. Aydin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Hydroxide ◽  
Silica Fume ◽  
Hardened Cement ◽  
Microstructural Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mechanical And Microstructural Properties ◽  
Scanning Electron

The effects of using different ratios of silica fume on the mechanical and microstructural properties of hardened cement paste and concrete were investigated in this study. Portland cement was replaced with 5%, 10%, 15%, and 20% silica fume (SF) by weight. Microstructural properties of obtained samples were investigated by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The XRD analysis showed that the ratio of calcium hydroxide (CH), which is produced by hydration, decreases depending on the concrete age and the amount of silica fume. The SEM analysis showed that the use of silica fume decreases gaps and calcium silicate hydrate (C-S-H) which is also a hydration production. Silica fume content of up to 15% improved the observed mechanical and microstructural properties of concrete. At the optimum value of 15%, improvement in the paste was observed due to the filler effect and the reaction between the silica fume and calcium hydroxide, leading to a reduction in calcium hydroxide in the concrete.

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