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Title: Texture formation in iron particles using mechanical milling with graphite as a milling aid

Abstract

Crystallographically anisotropic platelet iron particles were successfully prepared using a conventional ball mill with addition of graphite (Gp) particles. The morphological and structural changes resulting from the milling were investigated using scanning electron microscopy and X-ray diffraction. The spherical iron particles were plastically deformed into platelet shapes during the milling. Simultaneously, it is suggested that the size of the Gp particles decreased and adhered as nanoparticles on the surface of the iron particles. The adhered Gp particles affected the plastic deformation behavior of the iron particles: the (001) planes of α-iron were oriented parallel to the particle face, and no preferred in-plane orientation was observed. This study not only details the preparation of soft magnetic metal particles that crystallographically oriented to enhance their magnetic properties but also provides new insight into the activities of the well-established and extensively studied mechanical milling method.

Authors:
;  [1];  [2];  [3]
  1. Department of Mechanical Engineering, Gifu National College of Technology, 2236-2 Kamimakuwa, Motosu, Gifu 501-0495 (Japan)
  2. Department of Materials Science and Technology, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 (Japan)
  3. Toyota Physical and Chemical Research Institute, 41-1, Yokomichi, Nagakute, Aichi 480-1192 (Japan)
Publication Date:
OSTI Identifier:
22492347
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 9; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; GRAPHITE; IRON; MAGNETIC MATERIALS; MAGNETIC PROPERTIES; MILLING; NANOPARTICLES; PLASTICITY; SCANNING ELECTRON MICROSCOPY; SURFACES; TEXTURE; X-RAY DIFFRACTION

Citation Formats

Motozuka, S., Hayashi, K., Tagaya, M., and Morinaga, M.. Texture formation in iron particles using mechanical milling with graphite as a milling aid. United States: N. p., 2015. Web. doi:10.1063/1.4930915.
Motozuka, S., Hayashi, K., Tagaya, M., & Morinaga, M.. Texture formation in iron particles using mechanical milling with graphite as a milling aid. United States. doi:10.1063/1.4930915.
Motozuka, S., Hayashi, K., Tagaya, M., and Morinaga, M.. 2015. "Texture formation in iron particles using mechanical milling with graphite as a milling aid". United States. doi:10.1063/1.4930915.
@article{osti_22492347,
title = {Texture formation in iron particles using mechanical milling with graphite as a milling aid},
author = {Motozuka, S. and Hayashi, K. and Tagaya, M. and Morinaga, M.},
abstractNote = {Crystallographically anisotropic platelet iron particles were successfully prepared using a conventional ball mill with addition of graphite (Gp) particles. The morphological and structural changes resulting from the milling were investigated using scanning electron microscopy and X-ray diffraction. The spherical iron particles were plastically deformed into platelet shapes during the milling. Simultaneously, it is suggested that the size of the Gp particles decreased and adhered as nanoparticles on the surface of the iron particles. The adhered Gp particles affected the plastic deformation behavior of the iron particles: the (001) planes of α-iron were oriented parallel to the particle face, and no preferred in-plane orientation was observed. This study not only details the preparation of soft magnetic metal particles that crystallographically oriented to enhance their magnetic properties but also provides new insight into the activities of the well-established and extensively studied mechanical milling method.},
doi = {10.1063/1.4930915},
journal = {AIP Advances},
number = 9,
volume = 5,
place = {United States},
year = 2015,
month = 9
}
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  • The method of preparing carbon nanotube (CNT) by milling of graphite particles in water followed by high temperature annealing is proposed and the mechanism discussed. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) line broadening analysis reveal that cleavage of the graphite particles occurs preferentially along the out-of-plane {pi} bonds. Carbon K-edge near edge X-ray absorption fine structure (NEXAFS) of the milled graphite shows an increased sp3 character of the C=C bonds, but no major bonds rupture in the graphene sheets. The annealing at 1400 deg. C for 4 h of the milled graphite in argon results in formation ofmore » multiwalled carbon nanotubes accompanied with a number of coiled and twisted stacks of graphene sheets. The increased structural disorder of the milled graphite and presence of iron contaminations facilitate the rolling up of the cleaved graphene sheets during annealing.« less