Abstract
A nanocomposite of nanometer-sized magnetic granular ε-FexN embedded in a nonmagnetic amorphous boron nitride matrix was prepared by ball milling mixture of α-Fe and hexagonal boron nitride in argon atmosphere. The grain size of the ε-FexN alloy was about 10–20 nm. The nitrogen concentration in the ε-FexN alloy increases with extending milling time. Both thermodynamic calculation and the present experiment show that iron and nitrogen atoms have higher alloying driving force than iron and boron atoms. Analyses of thermodynamics and kinetics about formation of the ε-FexN alloy suggested that the formation of the ε-FexN alloy is related to amorphization of the hexagonal boron nitride and refinement of the α-Fe. It was found from the present experiment that a critical grain size of the α-Fe reacting with nitrogen in the amorphous boron nitride is about 8 nm.
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References
Horvath, M. P., Takacs, L., Magnetic nanocomposites by reaction milling,Scripta. Metall. and Mater., 1995, 33 (10/11): 1731.
Metzger, R. M., Bao, X. H., Megnetism of α″-Fe16N2,J. Appl. Phys., 1994, 76(10): 6626.
Chen, S. K., Jin, S., Kammlott, G. W.et al., Synthesis and magnetic properties of Fe4N and (Fe, Ni)4N sheets,J. Mag. and Mag. Mater., 1992, 110: 65.
Jack, K. H., The synthesis, structure and characterization of α″-Fe16N2,J. Appl. Phys., 1994, 77(10): 6620.
Jack, K. H., The iron-nitrogen system: the crystal structures of ε-phase iron nitrides,Acta Cryst., 1952, 5: 404.
Jack, K. H., The iron-nitrogen system: the preparation and crystal structures of nitrogen-austenite(γ) and nitrogen-matrensite(ά),Proc. Roy. Soc., A, 1951, 208: 200.
Kyu-Jin Kim, Kenji Sumiyama, Hideya Onoderaet al., Structure and magnetic properties of mechanically ground ε-Fe2.3N,Jpn. J. Appl. Phys., 1994, 33: 6539.
Zhang, L. D.,Nanostructured Materials (in Chinese), Shenyang: Liaoning Science and Technology Press, 1993, 21–23.
Niessen, A. K., de Boer, F. R., Miedema, A. R., Model prediction for the enthalpy of formation of transition metal alloys,CALPHAD, 1983, 17: 51.
Johnson, W. L., Thermodynamic and kinetic aspects of the crystal to glass transformation in metallic materials,Progress in Mater. Sci., 1986, 30: 81.
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Liu, L., Yao, B., Wang, H. et al. Formation of ε-FexN/BN magnetic nanocomposite and its thermodynamic and kinetic analyses. Chin. Sci. Bull. 43, 467–470 (1998). https://doi.org/10.1007/BF02883810
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DOI: https://doi.org/10.1007/BF02883810