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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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References

1Zhang, B. and Soffa, W.A.: Magnetic domains and coercivity in polytwinned ferromagnets. Phys. Status Solidi A 131, 707 (1992).CrossRefGoogle Scholar
2Klemmer, T., Hoydick, D., Okimura, H., Zhang, B., and Soffa, W.A.: Magnetic hardening mechanisms and coercivity in L10 ordered FePd ferromagnets. Scr. Metall. Mater. 33, 1793 (1995).CrossRefGoogle Scholar
3Deshpande, A.R., Xu, H., and Wiezorek, J.M.K.: Effects of grain size on coercivity of combined-reaction-processed FePd intermetallics. Acta Mater. 52, 2903 (2004).CrossRefGoogle Scholar
4Okumura, H., Soffa, W.A., Klemmer, T.J., and Barnard, J.A.: The relationship between structure and magnetic properties in nanostructured FePd ferromagnets. IEEE Trans. Magn. 34, 1015 (1998).CrossRefGoogle Scholar
5Klemmer, T.: Ph.D. Thesis, Materials Science and Engineering Department, University of Pittsburgh, 1995.Google Scholar
6Okumura, H.: Ph.D. Thesis, Materials Science and Engineering Department, University of Pittsburgh, 2000.Google Scholar
7Desphande, A.: Ph.D. Thesis, Materials Science and Engineering, University of Pittsburgh, 2005.Google Scholar
8J.Wiezorek, M.K.: Cold-working and annealing of L10-ordering iron-palladium base intermetallics. Mater. Sci. Forum 539-543, 1487 (2007).CrossRefGoogle Scholar
9Volkov, A.Yu., Greenberg, B.A., Kruglikov, N.A., Rodionova, L.A., Gushchin, G.M., Sakhanskaya, I.N., Vlasova, N.I., and Filippov, Yu. I.: Preparation and examination of a single-domain L10 superstructure in the FePd alloy. Phys. Met. Metall. 95, 355 (2003).Google Scholar
10Wang, L., Laughlin, D.E., Wang, Y., and Khachaturyan, A.G.: Effects of atomic ordering on the Curie temperature of FePd L10 type alloys. J. Appl. Phys. 93, 7984 (2003).CrossRefGoogle Scholar
11Vlasova, N.I., Kandaurova, G.S., and Schegoleva, N.N.: Effect of the parameters of twin microstructure on the magnetic-domain structure of CoPt-type alloys: A review. Fiz. Met. Metalloved. 90, 31 (2000).Google Scholar
12Jin, Y.M., Wang, Y.U., Khachaturyan, A.G., Wang, L., and Laughlin, D.E.: Development of magnetic domains in hard ferromagnetic thin films of polytwinned microstructure. J. Appl. Phys. 92, 7408 (2002).Google Scholar
13Ohodnicki, P.R. Jr, Deshpande, A., and Wiezorek, J.M.K.: Electron and magnetic force microscopy of bulk equiatomic Fe-Pd polycrystals with equiaxed microstructure. Microsc. Microanal. 10(Suppl 2), 2004.CrossRefGoogle Scholar
14Zhang, B.: Ph.D. Thesis, Materials Science and Engineering Department, University of Pittsburgh, 1991.Google Scholar
15Deshpande, A.R. and Wiezorek, J.M.K.: Magnetic age hardening of cold-deformed bulk equiatomic Fe-Pd intermetallics during isothermal annealing. J. Magn. Magn. Mater. 270, 157 (2004).CrossRefGoogle Scholar
16Al-Khafaji, M.A., Rainforth, W.M., Gibbs, M.R.J., Davies, J.A., and Bishop, J.E.L.: Magnetic force microscopy of nanocrystalline NdFeB ribbons: A study of tip-sample interaction using a wellcharacterised sample. J. Magn. Magn. Mater. 182, 111 (1998).CrossRefGoogle Scholar
17Crew, D.C., Lewis, L.H., and Panchanathan, V.: Multiscale magnetic domains observed in die-upset melt-spun magnets using magnetic force microscopy. J. Magn. Magn. Mater. 231, 57 (2001).CrossRefGoogle Scholar
18Folks, L. and Woodward, R.C.: The use of MFM for investigating domain structures in modern permanent magnet materials. J. Magn. Magn. Mater. 190, 28 (1998).CrossRefGoogle Scholar
19Hubert, A. and Schäfer, R.: Magnetic Domains The Analysis of Magnetic Microstructures (Springer, New York, 1998).Google Scholar
20Weller, D. and Moser, A.: Thermal processes and stability of longitudinal magnetic recording media. IEEE Trans. Magn. 35, 4423 (1999).CrossRefGoogle Scholar
21Zueco, E., Rave, W., Schäfer, R., Hubert, A., and Schultz, L.: Combined Kerr/magnetic force microscopy on NdFeB crystals of different crystallographic orientation. J. Magn. Magn. Mater. 190, 42 (1998).CrossRefGoogle Scholar
22Tanaka, K., Ichitsubo, T., Amano, M., Koiwa, M., and Watanabe, K.: Formation of mono-variant L10 structure on ordering of FePd under magnetic fields. Mater. Trans., JIM 41(8), 917 (2000).CrossRefGoogle Scholar
23Cullity, B.D.: Introduction to Magnetic Materials (Addison-Wesley Publishing Company, Reading, 1972).Google Scholar
24Chikazumi, S.: Physics of Ferromagnetism (John Wiley & Sons, Inc, New York, 1964), pp. 233–234, 240.Google Scholar
25Deshpande, A.R., Blachere, J.R., and Wiezorek, J.M.K.: Texture evolution in combined reaction transformed equiatomic ferromagnetic L10-ordered FePd intermetallics. Scr. Mater. 54, 955 (2006).CrossRefGoogle Scholar
26Deshpande, A.R. and Wiezorek, J.M.K.: Texture evolution in equiaxed polycrystalline L10-ordered FePd during coarsening at 600 °C. Z. Metallkd. 97(3), 304 (2006).CrossRefGoogle Scholar
27Ohodnicki, P., Webler, B., Deshpande, A.R., and Wiezorek, J.M.K.: Interpretation of magnetic force microscopy contrast using commercially available batch tips for investigation of surface magnetic-domain structure in polycrystalline bulk equiatomic L10 FePd. Metall. Mater. Trans. A 38, 2479 (2007).CrossRefGoogle Scholar
28Herzer, G.: Grain size dependence of coercivity and permeability in nanocrystalline ferromagnets. IEEE Trans. Magn. 26, 1397 (1990).CrossRefGoogle Scholar
29Ohodnicki, P.R.: B. Phil Thesis, Materials Science and Engineering Department, University of Pittsburgh, 2005.Google Scholar