Microstructure and magnetic properties of nanocrystalline cobalt–zirconium boride alloy prepared by melt spinning and subsequent annealing

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2019-08, Vol.125 (8), p.1-7, Article 502
• Main Authors: Motalebi, E., Tavoosi, M., Ghasemi, A., Gordani, G. R., Torkian, S., Loghman-Estarki, M. R.
• Format: Article
• Language: English
• Subjects: Annealing; Applied physics; Characterization and Evaluation of Materials; Cobalt base alloys; Cobalt compounds; Coercivity; Condensed Matter Physics; Crystallites; Crystals; Field emission microscopy; Machines; Magnetic properties; Magnetic saturation; Magnetism; Manufacturing; Materials science; Melt spinning; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Processes; Scanning electron microscopy; Surfaces and Interfaces; Thin Films; Vacuum induction melting; X-ray diffraction; Zirconium; Zirconium compounds
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-019-2784-5

The structural, thermal and magnetic characteristics of cobalt–zirconium boride (Co 80 Zr 18 B 2 ) alloy were investigated in this work. In this regards, cobalt–zirconium boride samples with different structures and crystallite sizes were prepared using a copper boat vacuum induction melting plus melt-spinning and subsequent annealing processes. Prepared samples were characterized using X-ray diffraction, field emission scanning electron microscopy, differential scanning calorimetry and vibrating sample magnetometer. According to X-ray diffraction results, cobalt–-zirconium (Zr 2 Co 11 ) single phase can successfully form by means of a melt-spinning process at a wheel speed of 40 m s −1 . The saturation magnetization and coercivity of this sample are 58 emu/g and 3 kOe, respectively, which exhibit a hard magnetic property. Cobalt–zirconium compound which formed during melt-spinning process was not stable and transformed to Co 23 Zr 6 during annealing process up to 500 °C. The maximum value of coercivity ( H c  = 3.4 kOe vs. 3 kOe for single Zr 2 Co 11 phase) is related to cobalt–zirconium boride alloy after annealing at 500 °C for 1 h.