Microstructure, phase evolution and magnetic properties of melt-spun SmCo6.8−xSnxZr0.2 (x = 0, 0.1 and 0.3) ribbons

► Effect of Sn on the characteristics of SmCo6.8Zr0.2 melt spun ribbons is studied. ► Wheel speed has significant effect on the grain size reduction of melt spun ribbons. ► Structural transformation from TbCu7 to Sm2Co17 -phase occurred with Sn addition. ► Ribbons with high Sn content showed improved hard magnetic properties. ► High coercivity of 10.4 kOe obtained for SmCo6.5Sn0.3Zr0.2 ribbons spun at 24 m/s.