Hyperfine Interactions 55 (1990) 1083-1088 1083 MAGNETIC AND MOSSBAUER STUDY OF AMORPHOUS Fe-Er-B RIBBONS J. TEILLET t, H. LASSRI 2, R. KRISHNAN 2 and A. LAGGOUN 1 i LP.C.M., INSA, B.P. 8, 76131 Mont-Saint-Aignan Cedex, France 2 Laboratoie de MagnOtisrne, 92195 Meudon Principal Cedex, France Amorphous FesoErxBz0_,. ribbons (0 < x < 4) have been studied by magnetization mea- surements up to 16 Teslas and by M~ssbauer experiments under applied fields. At any temperature, magnetic saturation is attained for 4 Teslas. Higher fields do not break the Er-Fe magnetic coupling. Erbium sublattice has a cone spin structure and iron sublanice is probably close to eollinear. 1. Introduction Metallic glasses based on transition metals and metalloids have been studied extensively. The influence of addition of various magnetic and non-magnetic atoms on the magnetic and transport properties has been well documented [1,2]. However studies on metallic glasses containing rare earth metals are very few [3]. We have reported recently on metallic glasses such as Fe-Er-B-Si [4] and Co-Er-B [5]. Another series, where B has been substituted by Er, has also been reported by us [6]. In this work, we describe magnetic and M6ssbauer studies on Fe80ErxB20_ ~. In both cases, high magnetic field was applied to obtain some information on the anisotropy and spin structure. 2. Experimental Amorphous Fe80Er.~B20_ x ribbons have been prepared by the usual melt-spin- ning technique under an inert atmosphere of argon. The amorphous structure of the samples was verified by X-rays diffraction and their composition determined by electron probe microanalysis. Magnetization was measured in the temperature range 4 K to 290 K, under applied fields up to 16 Teslas in SNCI Grenoble. The Curie temperature T~ and the crystallization temperature were determined using a vibration sample magnetometer fitted with an oven. M6ssbauer spectra were obtained with a conventional triangular waveform spectrometer using a source of 5VCo in a rhodium matrix. Mossbauer experiments under applied fields were performed at the Francis Bitter National Magnet Laboratory, M.I.T., Cambridge. Mossbauer samples made of parallel ribbons were set perpendicular to the 3' beam. 9 J.C. Baltzer A.G. Scientific Publishing Company