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

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 isNd(7)Fe(77)B(14)Mo(2) (similar to 1400 kA.m (1)) while the sample Nd8Fe74B14Nb4 has the lowest saturation value (similar to 600 kA.m (1)). The sample Nd7Fe75B14Ti4 exhibits the lowest value (similar to 400 kA.m (1)) while the d(8)Fe(74)B(14)Ti(4)exhibits the highest value (similar to 700 kA.m (1)) and the maximum (B.H)(max) value similar to 110 kJ.m (3). The use of different experimental techniques, such as X-ray diffraction, Mossbauer 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. (C) 2018 Elsevier B.V. All rights reserved.