Effects of W substitution on the magnetic properties, phase evolution and microstructure of rapidly quenched Co80Zr18B2 alloy

• Published in: Journal of magnetism and magnetic materials Vol. 368; pp. 116 - 120
• Main Authors: Hou, Zhipeng, Yang, Chongli, Xu, Shifeng, Zhang, Jinbao, Liu, Dan, Su, Feng, Wang, Wenquan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.11.2014; Elsevier
• Subjects: Co-Zr-W-B alloys; Coercivity; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Domain effects, magnetization curves, and hysteresis; Exact sciences and technology; Heat treatment; Magnetic properties and materials; Magnetization curves, magnetization reversal, hysteresis, barkhausen and related effects; Melt-spun ribbons; Physics; Co-Zr-W-B alloys; Heat treatment; Melt-spun ribbons; Coercivity; Scanning electron microscopy; Magnetization; Impurity density; Thermomagnetic effects; Tungsten additions; Melt spinning; XRD; Heat treatments; Boron alloys; Cobalt base alloys; Magnetic anisotropy; Coercive force; Microstructure; Exchange interactions; Transition element alloys; Zirconium alloys
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2014.05.024

The effects of a partial substitution of W for Zr on the magnetic properties, phase evolution, and microstructure of Co80Zr18−xWxB2 (x=0, 1, 2 and 3) melt-spun ribbons are investigated in this paper. For the as-spun samples, the optimal magnetic properties of iHc=6.6kOe and (BH)max=4.5MGOe are achieved in the Co80Zr16W2B2. Thermomagnetic analysis (TMA) and x-ray diffraction (XRD) results suggest that the as-spun Co80Zr16W2B2 mainly comprises of hard magnetic phase. Scanning electron microscope (SEM) results indicate that W addition refines the microstructure, which results in an increase in the intergrain exchange interaction. The effects of heat treatment on the magnetic properties of as-spun Co80Zr18−xWxB2 (x=0, 1, 2 and 3) are also studied. The maximum iHc of 7.3kOe with a (BH)max of 3.8MGOe is obtained in the Co80Zr16W2B2 after a heat treatment at 550°C. The origin of coercivity enhancement in Co80Zr16W2B2 is ascribed to the increase in magnetocrystalline anisotropy field (Ha) of hard magnetic phase. •Addition of W improved magnetic properties of Co80Zr18B2 significantly.•The addition of W reduced the grain size of hard magnetic phase.•A maximum coercivity of 7.3kOe was obtained in the Co80Zr16W2B2 ribbons.