Hard magnetic properties in melt-spun Co80Zr18−xMoxB2 alloys

Co80Zr18−xMoxB2 (x=1, 2, 3, 4) alloys have been produced by melt-spinning followed by heat treatment. We get a high coercivity of 6.3 kOe for the sample with x=2. Heat treatment of Co–Zr–Mo–B melt-spun ribbons results in an increase in coercivity. Co80Zr16Mo2B2 ribbons, annealed at 600 °C for 30 min, exhibit the optimized magnetic properties of Hc=6.8 kOe, σr=37.14 emu/g and (BH)max=2.85 MGOe. The hysteresis curves of the studied ribbons are very smooth and their ratios σr/σs exceed 0.6.