Structural Characterization and Ordering Transformation of Mechanically Alloyed Nanocrystalline Fe-28Al Powder
Authors
Abstract:
The synthesis of nanocrystalline Fe3Al powder by mechanical alloying as well as the structural ordering of the synthesized Fe3Al particles during the subsequent thermal analysis were investigated. Mechanical alloying was performed up to 100 hours using a planetary ball mill apparatus with rotational speed of 300 rpm under argon atmosphere at ambient temperature. The synthesized powders were characterized using X-ray diffraction, SEM observations and differential scanning calorimetry (DSC). The results show that the A2-type Fe3Al with disordered bcc structure is only formed after 70 hours milling. The corresponding lattice strain, mean crystallite and particle sizes for the 70 hours milled Fe3Al powder were determined as 2.5%, 10 and 500 nm, respectively. The subsequent heating during DSC causes a DO3-type Fe3Al ordering in 70 and 100 hours milled powders, however in 40 hours milled powder it only assists for the formation of disordered solid solution. Longer milling time induces a large amount of lattice strain in Fe3Al powder particles and consequently facilitates the atomic diffusion thus decreases the activation energy of ordering. The activation energy for ordering transformation of 100 hours Fe3Al milled powder was calculated as 152.1 kJ/mole which is about 4 kJ/mole lower than that for 70 hours milled powder.
similar resources
structural characterization and ordering transformation of mechanically alloyed nanocrystalline fe-28al powder
the synthesis of nanocrystalline fe3al powder by mechanical alloying as well as the structural ordering of the synthesized fe3al particles during the subsequent thermal analysis were investigated. mechanical alloying was performed up to 100 hours using a planetary ball mill apparatus with rotational speed of 300 rpm under argon atmosphere at ambient temperature. the synthesized powders were cha...
full textXANES of Mechanically Alloyed Y-Fe System
We have measured X-ray absorption near edge structure (XANFS) of mechanically alloyed YzFe and YFez system as a fundion of milling time. An amorphous phase is obtained by mechanical alloying for 100 hours in the YzFe system and for 500 hours in the YFez system. In both systems the intensity of Fe Is-4pn transition grows up significantly with increasing the milling time and approaches to that of...
full textNano-sized Superlattice Clusters Created by Oxygen Ordering in Mechanically Alloyed Fe Alloys
Creating and maintaining precipitates coherent with the host matrix, under service conditions is one of the most effective approaches for successful development of alloys for high temperature applications; prominent examples include Ni- and Co-based superalloys and Al alloys. While ferritic alloys are among the most important structural engineering alloys in our society, no reliable coherent pr...
full textStructural Evolution during Milling, Annealing, and Rapid Consolidation of Nanocrystalline Fe–10Cr–3Al Powder
Structural changes during the deformation-induced synthesis of nanocrystalline Fe-10Cr-3Al alloy powder via high-energy ball milling followed by annealing and rapid consolidation by spark plasma sintering were investigated. Reduction in crystallite size was observed during the synthesis, which was associated with the lattice expansion and rise in dislocation density, reflecting the generation o...
full textNanocrystalline Alloys: Enhanced Strengthening Mechanisms and Mechanically-Driven Structural Evolution
Nanocrystalline materials have experienced a great deal of attention in recent years, largely due to their impressive array of physical properties. In particular, nanocrystalline mechanical behavior has been of interest, as incredible strengths are predicted when grain size is reduced to the nanometer range. The vast majority of research to this point has focused on quantifying and understandin...
full textMy Resources
Journal title
volume 49 issue 2
pages 112- 119
publication date 2016-12-01
By following a journal you will be notified via email when a new issue of this journal is published.
Hosted on Doprax cloud platform doprax.com
copyright © 2015-2023