Enhancing the coercivity of Nd-Cu-diffused Nd-Fe-B permanent magnets by Nb-assisted grain boundary pinning. Issue 12 (2nd December 2022)

• Record Type: Journal Article
• Authors: Siva Kumar, M. B.; Prabhu, D.; Sadhasivam, M.; Manjusha, B.; Chandrasekaran, N.; Pradeep, K. G.; Sundararajan, G.; Gopalan, R.
• Is Part Of: Materials research letters. Volume 10:Issue 12(2022)
• Page Start: 780
• Page End: 787
• Publication Date: 2022-12-02
• Subjects: Grain boundary -- diffusion -- Atom Probe Tomography -- Nb clusters -- Nd-Fe-B magnet; Materials science -- Research -- Periodicals; Biomedical materials -- Research -- Periodicals; Composite materials -- Research -- Periodicals; Biomedical materials -- Research; Composite materials -- Research; Materials science -- Research; Periodicals; 620.1105
• DOI: 10.1080/21663831.2022.2104139
• Languages: English
• ISSNs: 2166-3831

Abstract

Abstract : We report the effect of grain boundary diffusion of the Nd-Cu eutectic phase and the influence of Nb on the microstructure and magnetic properties of Nd-Fe-B melt-spun ribbons. The Atom probe tomography analysis indicated the presence of Nb clusters (∼10 nm), which possibly restricts grain growth during diffusion annealing while facilitating Nd-Cu grain boundary decoration. Correspondingly, the coercivity was enhanced from the initial 1.2 T of the as-prepared to 2.1 T for the 20 wt.% Nd-Cu diffusion annealed (600°C, 2 h). Incidentally, the as-diffused sample exhibited a high coercivity of ∼1 T at 150°C, making it suitable for high-temperature applications. GRAPHICAL ABSTRACT: UF0001