Title :
Effect of nitrogen and methane on the structural and magnetic properties of RFe2 (R=Y, Tb and Dy)
Author :
Singleton, E.W. ; Tang, Z.X. ; Hadjipanayis, G.C. ; Papaefthymiou, V.
Author_Institution :
Dept. of Phys. & Astron., Delaware Univ., Newark, DE, USA
fDate :
11/1/1993 12:00:00 AM
Abstract :
Rare earth alloys (R=Y, Tb, and Dy) with MgCu2 type crystal structure and the effect of heat treatment in methane and nitrogen gas is studied. The structural and magnetic properties are characterized by Mossbauer spectroscopy. For low heat treatment temperatures (250 to 350 °C), C(N) are absorbed resulting in an increased lattice constant. For intermediate heat treatment temperatures, a metastable phase forms in the methane heat treated samples which enhances hard magnetic properties with room temperature coercive fields of 1.4 and 1.1 kOe found in coarse powders of Tb-Fe-C and Dy-Fe-C, respectively. For high heat treatment temperatures (above 450°C), decomposition to RC(RN) and α-Fe occurs
Keywords :
Mossbauer effect; coercive force; crystal atomic structure of alloys; ferromagnetic properties of substances; heat treatment; iron alloys; lattice constants; nitridation; permanent magnets; rare earth alloys; α-Fe; 20 degC; 250 to 450 degC; C absorption; Dy-Fe-C; Dy-Fe-N; MgCu2 type crystal structure; Mossbauer spectroscopy; N absorption; N effects; RFe2; Tb-Fe-C; Tb-Fe-N; Y-Fe-C; Y-Fe-N; coarse powders; hard magnetic properties; heat treatment; lattice constant; low heat treatment temperatures; magnetic properties; metastable phase; methane; methane heat treated samples; room temperature coercive fields; structure; Electromagnetic wave absorption; Heat treatment; Lattices; Magnetic field measurement; Magnetic properties; Magnetic variables measurement; Metastasis; Nitrogen; Temperature distribution; X-ray diffraction;
Journal_Title :
Magnetics, IEEE Transactions on
