Influence of Nb, Mo, and Ti as doping metals on structure and magnetic response in NdFeB based melt spun ribbons

• Published in: Journal of magnetism and magnetic materials Vol. 462; pp. 83 - 95
• Main Authors: Derewnicka-Krawczyńska, D., Ferrari, S., Bilovol, V., Pagnola, M., Morawiec, K., Saccone, F.D.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15-09-2018; Elsevier BV
• Subjects: Chemical properties; CMOS; Coercivity; Comparative analysis; Doping; Doping metals; Grain boundaries; Hard magnetic materials; Magnetic fields; Magnetic measurement; Magnetic properties; Magnetic saturation; Melt spinning; Molybdenum; Mossbauer spectroscopy; NdFeB melt spun ribbons; Niobium; Organic chemistry; Rapid quenching (metallurgy); Ribbons; Spinning (metals); Tapes (metallic); Titanium; X ray photoelectron spectroscopy; X-ray diffraction; NdFeB melt spun ribbons; Doping metals; Hard magnetic materials; Comparative analysis; Magnetic properties
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2018.05.004

•It’s shown a comparative analysis of magnetic measurements done over rapidly quenched melt-spinning alloyed ribbons.•Are studied the magnetic properties such as coercivity, saturation magnetization and energy product (B.H)max over annealed ribbons.•The energy product (B.H)max achieves the maximum value in the sample Nd8Fe74B14Ti4.•The obtained magnets have the highest energy product at ambient temperature and can use the electrical energy very efficiently in specific applications.
In this work, it is shown a comparative analysis of magnetic measurements that has been done over rapidly quenched melt-spinning alloyed ribbons with the formula NdyFe(86−y−x)B14Mx (X = 2, 4; Y = 7,8; M = Nb, Mo, Ti). The magnetic properties such as coercivity, saturation magnetization and energy product (B.H)max are analyzed for ribbons annealed for 20 min at 953 K in each case. It is observed that the sample with the highest saturation isNd7Fe77B14Mo2 (∼1400 kA.m−1) while the sample Nd8Fe74B14Nb4 has the lowest saturation value (∼600 kA.m−1). The sample Nd7Fe75B14Ti4 exhibits the lowest value (∼400 kA.m−1) while the Nd8Fe74B14Ti4 exhibits the highest value (∼700 kA.m−1) and the maximum (B.H)max value ∼110 kJ.m−3. The use of different experimental techniques, such as X-ray diffraction, Mössbauer spectroscopy, X-ray photoelectron spectroscopy, helped us to comprehend how M doping has influenced in a broad set of physical and chemical properties (e.g. crystalline phases, grain boundary doping enrichment, etc.) and how they correlate with the various observed magnetic features for these ribbons.