Magnetoresistance and exchange bias in high Mn content melt-spun Mn46Ni42Sn11Sb1 alloy ribbon*

Highly textured Heusler alloy Mn46Ni42Sn11Sb1 ribbons were prepared by melt spinning. The annealed high Mn content Mn46Ni42Sn11Sb1 ribbon cross-section microstructure, crystal structure, martensitic transformation (MT), and magnetoresistance (MR) properties were investigated. The MR in the annealed ribbon was assessed by the magnetic field direction perpendicular to the ribbon surface with the magnetic field up to 30 kOe. The large negative value of 25% for MR was obtained at 244 K. The exchange bias (EB) effects of the as-spun and annealed ribbons were investigated. After annealing, the EB effects have been improved by about 25 Oe at the temperature of 50 K. The magnetizations have increased approximately by 10% more than the as-spun ribbon.