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Compositional and microstructural evolution during annealing of Terfenol-D nanoparticulate films

  • James Ma (a1), Michael F. Becker (a2), John W. Keto (a3) and Desiderio Kovar (a4)


Although highly magnetostrictive thin films of Terfenol-D have been produced by a variety of methods, high-quality thick films have proved to be far more challenging to produce. To date, thick film processes have resulted in nanoparticulate films that contain significant porosity that reduces stiffness and results in oxidation and poor magnetostrictive performance. With the goal of understanding microstructural and compositional factors that affect performance, nanoparticulate Terfenol-D thick films were produced by laser ablation of microparticle aerosols combined with supersonic impaction. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, x-ray photon spectroscopy, and magnetic measurements were performed on nanoparticles and on films as-deposited and after annealing in vacuum or in a reducing atmosphere. These measurements show that segregation occurs during oxidation of the films, prior to annealing, and results in films with poor magnetostriction. The segregation persists during annealing with no visible changes to the morphology or density of the nanoparticulate films exposed to temperatures as high as 800 °C. These results suggest that oxidation and segregation must be avoided to produce highly magnetostrictive thick films.


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1.Quandt, E., Gerlach, B., and Seemann, K.: Preparation and applications of magnetostrictive thin films. J. Appl. Phys. 76, 7000 (2004).
2.Wada, M., Uchida, H-H., Matsumura, Y., Uchida, H., and Kaneko, H.: Preparation of Films of (Tb, Dy)Fe2 Giant magnetostrictive alloy by ion beam sputtering process and their characterization. Thin Solid Films. 281-282, 503 (1996).
3.Ma, J., O’Brien, D.T., and Kovar, D.: Amorphous Terfenol-D films using nanosecond pulsed laser deposition. Thin Solid Films. 5187, 319 (2009).
4.Ma, J., Becker, M.F., Keto, J.W., and Kovar, D.: Laser ablation of nanoparticles and nanoparticulate, thick Fe1.92Tb0.3Dy0.7 films. J. Mater. Res. 25, 1733 (2010).
5.Grabham, N.J., White, N.M., and Beeby, S.P.: Thick-film magnetostrictive material for MEMS. Electron. Lett. 36, 332 (2000).
6.van Dover, R.B., Gyorgy, E.M., Frankenthal, R.P., Hong, M., and Siconolfi, D.J.: Effect of oxidation on the magnetic properties of unprotected TbFe thin films. J. Appl. Phys. 59, 1291 (1986).
7.Wada, M., Uchida, H.H., and Uchida, H.: Effects of the compositional change and the contamination on the magnetic and magnetostrictive characteristics of TbxDy1-xFe2 (x = 0–1) films. J. Alloy. Comp. 258, 174 (1997).
8.MacKenzie, J.K.: The elastic constants of a solid containing spherical holes. Proc. Phys. Soc. London B63, 2 (1950).
9.du Tremolet de Lacheisserie, E. and Peuzin, J.C.: Magnetostriction and internal stresses in thin films: The cantilever method revisited. J. Magn. Magn. Mater. 136, 189 (1994).
10.Henneke, D.E.: Laser Ablation of a Terfenol-D (Tb0.3Dy0.7Fe1.92) Microparticle Aerosol and Subsequent Supersonic Nanoparticle Impaction for Magnetostrictive Thick Films. Ph.D. Dissertation, University of Texas at Austin, Austin, TX, 2001.
11.Huang, C., Nichols, W.T., O’Brien, D.T., Becker, M.F., Keto, J.W., and Kovar, D.: Supersonic jet deposition of silver nanoparticle aerosols: Correlations of impact conditions and film morphologies. J. Appl. Phys. 101, 064902 (2007).
12.De La Mora, J.F., Hering, S.V., Rao, N., and McMurry, P.H.: Hypersonic impaction of ultrafine particles. J. Aerosp. Sci. 21, 169 (1990).
13.O’Brien, D.T., Ph.D. Dissertation, University of Texas at Austin, Austin, TX, 2006.
14.Nichols, W.T., Malyavanatham, G., Henneke, D.E., O’Brien, D.T., Becker, M.F., and Keto, J.W.: Bimodal nanoparticle size distributions produced by laser ablation of microparticles in aerosols. J. Nanopart. Res. 4, 423 (2002).
15.Nichols, W.T., Malyavanatham, G., Henneke, D.E., Brock, J.R., Becker, M.F., Keto, J.W., and Glicksman, H.D.: Gas and pressure dependence for the mean size of nanoparticles produced by laser ablation of flowing aerosols. J. Nanopart. Res. 2, 141 (2000).
16.Bhargava, G., Gouzman, I., Chun, C.M., Ramanarayanan, T.A., and Bernasek, S.L.: Characterization of the “native” surface thin film on pure polycrystalline iron: A high resolution XPS and TEM study. Appl. Surf. Sci. 253, 4322 (2007).
17.Padalia, B.D., Lang, W.C., Norris, P.R., Watson, L.M., and Fabian, D.J.: X-ray photoelectron core-level studies of the rare-earth metals and their oxides. Proc. R. Soc. London, A Math. Phys. Sci. 354, 269 (1977).
18.Sarma, D.D. and Rao, C.N.R.: XPES studies of oxides of second- and third-row transition metals including rare earths. J. Electron Spectrosc. Relat. Phenom. 20, 25 (1980).
19.Albert, A.D., Becker, M.F., Keto, J.W., and Kovar, D.: Low temperature, pressure-assisted sintering of nanoparticulate silver films. Acta Mater. 56, 1820 (2008).
20.Mei, W., Umeda, T., Zhou, S., and Wang, R.: Preparation and magnetostriction of Tb–Dy–Fe sintered compacts. J. Magn. Magn. Mater. 174, 100 (1997).
21.Ried, K., Schnell, M., Schatz, F., Hirscher, M., Ludescher, B., Sigle, W., and Kronmueller, H.: Crystallization behaviour and magnetic properties of magnetostrictive TbDyFe Films. Phys. Status Solidi A 167, 195 (1998).
22.Wada, M., Uchida, H., and Kaneko, H.: Effect of annealing treatment of the Tb0.3Dy0.7Fe2 thin films on the magnetic and magnetostrictive characteristics. J. Alloy. Comp. 258, 169 (1997).
23.Clark, A.E. and Belson, H.S.: Giant room-temperature magnetostrictions in TbFe2 and DyFe2. Phys. Rev. B 5, 3642 (1972).
24.Herzer, G.: Anisotropies in soft magnetic nanocrystalline alloys. J. Magn. Magn. Mater. 294, 99 (2005).
25.Cushing, B.L., Golub, V.O., Henry, M., Oliva, B.L., Cook, E., Holmes, C.W., and O’Connor, C.J.: Effects of annealing on the magnetic properties, size and strain of gold-coated permalloy nanoparticles. Nanotechnology 16, 1701 (2005).
26.Green, D.G.: An introduction to the mechanical properties of ceramics (Cambridge Univ. Press, Cambridge, England, 1998).
28.Rahaman, M.N.: Ceramic Processing and Sintering (Marcel Dekker, New York, NY, 2003).


Compositional and microstructural evolution during annealing of Terfenol-D nanoparticulate films

  • James Ma (a1), Michael F. Becker (a2), John W. Keto (a3) and Desiderio Kovar (a4)


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