Influence of W Addition on Phase Constitution, Microstructure and Magnetic Properties of the Nanocrystalline Pr9Fe65WxB26-x (Where: x = 2, 4, 6, 8) Alloy Ribbons

Katarzyna Filipecka; Piotr Pawlik; Andrzej Kozdraś; Waldemar Kaszuwara; Jarosław Ferenc; Jacek Filipecki

doi:10.3390/ma13102229

Influence of W Addition on Phase Constitution, Microstructure and Magnetic Properties of the Nanocrystalline Pr₉Fe₆₅W_xB_26-x (Where: x = 2, 4, 6, 8) Alloy Ribbons

Materials (Basel). 2020 May 13;13(10):2229. doi: 10.3390/ma13102229.

Authors

Katarzyna Filipecka^{1

2}, Piotr Pawlik², Andrzej Kozdraś³, Waldemar Kaszuwara⁴, Jarosław Ferenc⁴, Jacek Filipecki¹

Affiliations

¹ Faculty of Mathematics and Natural Science, Jan Dlugosz University, Armii Krajowej 13/15, 42-200 Czestochowa, Poland.
² Faculty of Production Engineering and Materials Technology, Czestochowa University of Technology, Armii Krajowej 19, 42-200 Czestochowa, Poland.
³ Faculty of Production Engineering and Logistics, Opole University of Technology, Ozimska 75, 45-370 Opole, Poland.
⁴ Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw, Poland.

Abstract

The aim of the present work was to investigate an influence of W addition on the phase constitution, microstructure and magnetic properties of the Pr₉Fe₆₅W_xB_26-x (where: x = 2, 4, 6, 8) alloy ribbons. Ribbons were obtained using the melt-spinning technique under low pressure of Ar. The as-cast samples were fully amorphous and revealed soft magnetic properties. These facts were confirmed by X-ray diffractometry, Mössbauer spectroscopy and magnetic measurements. Differential scanning calorimetry and differential thermal analysis allowed us to determine the thermal stability parameters of the amorphous phase. The Kissinger plots were constructed in order to calculate the activation energies for crystallization. Heat treatment carried out at various temperatures caused changes in the phase constitution and magnetic properties of the alloys. The phase analysis has shown the presence of the hard magnetic Pr₂Fe₁₄B and paramagnetic Pr_1+xFe₄B₄ phases. Additionally, for the x = 2 and x = 6 alloys, a crystallization of soft magnetic Fe₂B and α-Fe phases was observed. The Mössbauer spectroscopy allowed us to determine the volume fractions of constituent phases formed during annealing. The microstructure of annealed ribbons was observed using transmission electron microscopy.

Keywords: Mössbauer spectroscopy; X-ray diffraction; crystallization; magnetic properties; permanent magnets; rapid solidification; rare earth; thermal stability; transmission electron microscopy.