Skip to main content Accessibility help
×
Home
Hostname: page-component-cf9d5c678-vbn2q Total loading time: 0.239 Render date: 2021-07-29T13:33:45.445Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "metricsAbstractViews": false, "figures": true, "newCiteModal": false, "newCitedByModal": true, "newEcommerce": true, "newUsageEvents": true }

Article contents

Direct Observation of Reverse Magnetic Domain and Magnetic Domain Wall Motion in Nd-Fe-B Magnet at High Temperature by Lorentz Microscop

Published online by Cambridge University Press:  14 January 2016

Toshimasa Suzuki
Affiliation:
Materials Research and Development Laboratory, Japan Fine Ceramics Center (JFCC), Nagoya, 456-8587, Japan.
Koichi Kawahara
Affiliation:
Materials Research and Development Laboratory, Japan Fine Ceramics Center (JFCC), Nagoya, 456-8587, Japan.
Masaya Suzuki
Affiliation:
Materials Research and Development Laboratory, Japan Fine Ceramics Center (JFCC), Nagoya, 456-8587, Japan.
Kenta Takagi
Affiliation:
Inorganic Functional Materials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya, 463-8560, Japan.
Kimihiro Ozaki
Affiliation:
Inorganic Functional Materials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya, 463-8560, Japan.
Corresponding
E-mail address:
Get access

Abstract

We conducted the in-situ observations of the magnetic domain structure change in Nd-Fe-B magnets at high temperature by transmission electron microscopy (TEM) / Lorentz microscopy with applying an external magnetic field. Prior to observation, a thin foil was magnetized by an external magnetic field of 2.0 T to almost saturation, then the magnetic domain structures were observed by the Fresnel mode with in-situ heating. At 225°C, reverse magnetic domains were found to generate in the thin foil sample without applying an external magnetic field. When we applied a magnetic field on the same direction to the pre-magnetization direction at 225°C, one magnetic domain wall was pinned by a grain boundary and the other magnetic domain wall moved. As the results, the reverse magnetic domain shrank then annihilated. When we cut the applied magnetic field, the reverse magnetic domain generated at almost the same location. On the other hand, when we applied a magnetic field to the foils in the opposite direction, the reverse domain started to grow, i.e., magnetic domain walls started to move. The observation results of the shrink or growth of the reverse domain showed that the pinning effect of grain boundary against domain wall motion would be different depending on the applied magnetic field direction. Moreover, domain walls was observed to be pinned by grain boundaries at elevated temperature, so that the coercivity of Nd-Fe-B magnet would occur by pinning mechanism.

Type
Articles
Copyright
Copyright © Materials Research Society 2016 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ramesh, R., Thomas, G., and Ma, B. M., J. Appl. Phys. 64, 6417 (1988).
Sepehri-Amin, H., Ohkubo, T., Nishiuchi, T., Hirosawa, S., and Hono, K., Scr.Mater. 63, 1124 (2010).CrossRef
Akiya, T., Liu, J., Sepehri-Amin, H., Ohkubo, T., Hioki, K., Hattori, A., Hono, K., J. Appl. Phys. 115, 17A766 (2014).CrossRef
Hono, K., Sepehri-Amin, H., Scr.Mater. 67, 530 (2012).CrossRef
Park, H. S., Park, Y.-G., Gao, Y., Shondo, D. and Inoue, M., J. Appl. Phys. 97, 033908 (2005).CrossRef
Li, W.F., Ohkubo, T., Hono, K., Nishiuchi, T., and Hirosawa, S., J. Appl. Phys. 105, 07A706 (2009).CrossRef
Takagi, K., Akada, M., Soda, R., Ozaki, K., J. Magn. Magn. Mater. 393, 461 (2015).CrossRef
Suzuki, T., Kawahara, K., Tanaka, H. and Ozaki, K. in State-of-the-Art Developments in Materials Characterization, edited by Barabash, R., Benning, L.G., Genc, A., Kim, Y., Lereu, A., Li, D., Lienert, U., Liss, K.D., Ohnuma, M., Ovchinnikova, O., Passian, A., Rimer, J.D., Tetard, L., Thundat, T., Zenobi, R. and Zorba, V., (Mater. Res. Soc. Symp. Proc. 1754, 2015) opl. 2015. 585.Google Scholar
Li, W. F., Ohkubo, T., Hono, K., Niniushi, T., and Hirosawa, S., Appl, Phys. Lett. 93, 052505 (2008).CrossRef
Matsuura, Y., Kitai, N., Ishii, R., Natsumeda, T., Hoshijima, J., J. Magn. Magn. Mater. 336, 88 (2013).CrossRef
Matsuura, Y., Ishii, R., J. Magn. Magn. Mater. 346, 113 (2013).CrossRef

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Direct Observation of Reverse Magnetic Domain and Magnetic Domain Wall Motion in Nd-Fe-B Magnet at High Temperature by Lorentz Microscop
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Direct Observation of Reverse Magnetic Domain and Magnetic Domain Wall Motion in Nd-Fe-B Magnet at High Temperature by Lorentz Microscop
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Direct Observation of Reverse Magnetic Domain and Magnetic Domain Wall Motion in Nd-Fe-B Magnet at High Temperature by Lorentz Microscop
Available formats
×
×

Reply to: Submit a response

Please enter your response.

Your details

Please enter a valid email address.

Conflicting interests

Do you have any conflicting interests? *