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Magnetic force microscopy of combined reaction-processed polycrystalline equiatomic bulk L10 FePd

Published online by Cambridge University Press:  31 January 2011

Paul R. Ohodnicki ,
Anirudha Desphande ,
Jorg M.K. Wiezorek  and
Timothy J. Klemmer
Paul R. Ohodnicki*
Affiliation:
Mechanical Engineering and Materials Science Department, University of Pittsburgh, Pennsylvania 15213
Anirudha Desphande
Affiliation:
Mechanical Engineering and Materials Science Department, University of Pittsburgh, Pennsylvania 15213
Jorg M.K. Wiezorek
Affiliation:
Mechanical Engineering and Materials Science Department, University of Pittsburgh, Pennsylvania 15213
Timothy J. Klemmer
Affiliation:
Seagate Research, Pittsburgh, Pennsylvania 15222-4215
*
a) Address all correspondence to this author. Present address: Materials Science and Engineering Department, Carnegie Mellon University, PA 15213. e-mail: [email protected]
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Abstract

In this work, the correlation between magnetic-domain structure and microstructure in combined reaction-processed equiatomic L10 FePd has been investigated using magnetic force microscopy. The microstructure consisted of approximately equiaxed grains with an average grain size of ∼1 μm and a grain size distribution ranging from below the theoretical critical domain size (Dcrit∼0.2–0.3 μm) up to approximately 5 μm in diameter. The domain structure was characterized as “mixed” in nature, consisting of smaller single-domain grains, larger multidomain grains, and a larger scale interaction domain structure encompassing many grains. The domain boundaries separating interaction domains tended to lie along grain boundaries, and it is proposed that the observed interaction domains should be considered in descriptions of the magnetization and magnetization reversal behavior of this material. In particular, pinning of interaction domain walls by intragranular features of the microstructure such as grain boundaries and single-domain grains could play a role in the measured coercivities.

Keywords

Magnetic propertiesMicrostructureScanning-probe microscopy (SPM)
Type
Articles
Information
Journal of Materials Research , Volume 24 , Issue 8 , August 2009 , pp. 2677 - 2687
Copyright
Copyright © Materials Research Society 2009

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